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Making the case for the capabilities enabled by CTV+CSFS MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_3298_303281863.1750953760462" X-Original-Sender: joshsdoman@gmail.com Precedence: list Mailing-list: list bitcoindev@googlegroups.com; contact bitcoindev+owners@googlegroups.com List-ID: X-Google-Group-Id: 786775582512 List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , X-Spam-Score: -0.5 (/) ------=_Part_3298_303281863.1750953760462 Content-Type: multipart/alternative; boundary="----=_Part_3299_2005966468.1750953760462" ------=_Part_3299_2005966468.1750953760462 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable > The ability to commit to the exact transaction spending an output is=20 useful to reduce interactivity in second-layer protocols. Where do you stand on explicit commitments to neighbor prevouts? My=20 understanding is that this capability would be extremely useful, for BitVM= =20 and for making offers to buy UTXOs. If the goal is to commit to the "exact= =20 transaction spending an output," CTV alone wouldn't quite get you there. On Wednesday, June 25, 2025 at 5:28:02=E2=80=AFPM UTC-4 Ethan Heilman wrote= : > > Why not even CAT, which is a neat tool in many situations and would let= =20 > ZK people experiment with validation rollups? And at this point, it would= =20 > seem wiser to just work on a sane Bitcoin Script replacement rather than= =20 > throwing buckets of opcodes at it and hoping it holds off. > > A Bitcoin Script replacement is likely to be a lot of work and many of > the features will be informed by what people are building at the time > it is designed. Merging a low implementation complexity opcode like > OP_CAT (BIP-347) would provide useful data to inform a Bitcoin Script > replacement. > > In addition to allowing ZK people to experiment, OP_CAT also has many > simple use cases that improve everyday boring tapscripts. > > > Sure, but I=E2=80=99d argue that the presence of risk now is a reason t= o be more=20 > cautious about adding to it, rather than accepting it as inevitable. > > Addressing MEVil, if addressing MEVil is considered an important goal, > requires being proactive and enabling the ability to build better > protocols on Bitcoin. This is because, all things being equal, > building a protocol that doesn't care about MEVil resistance is easier > and requires less scripting functionality than one that does. > > On Wed, Jun 25, 2025 at 12:54=E2=80=AFPM 'Antoine Poinsot' via Bitcoin > Development Mailing List wrote: > > > > Thanks for sharing some objections. Here is my attempt at addressing=20 > them. > > > > > ISTM even something as simple as a rate-limit requires more=20 > full-featured introspection than only > > > "commit to the exact next transaction" can provide. For example, a=20 > trivial construction would be > > > something which requires that transactions spending an output have an= =20 > output which claims at least > > > Amount - Rate, which requires both more full-featured introspection a= s=20 > well as a bit of math. > > > > Yes. These capabilities are really only useful for reducing=20 > interactivity in second-layer protocols. > > They do not (reasonably) help for vaults and we do not claim it as a us= e=20 > case. > > > > Previous efforts to promote opcodes implementing those capabilities hav= e=20 > unfortunately fallen into > > the trap of overpromising and claiming use cases they do not really=20 > enable. But this should not make > > us overlook what they are really good at: interactivity reduction. > > > > Do you think that the use cases presented in OP, if demonstrated, are= =20 > not enough to warrant soft > > forking in a primitive enabling them? > > > > > Given one of the loudest groups advocating for the additional feature= s=20 > of CTV+CSFS are enterprise > > > or large-value personal custody providers > > > > Yes. We intentionally do not mention vaults as a use case in our=20 > steelman. We should not change > > Bitcoin on the basis of misleading use cases. If people are interested= =20 > in vaults, they should > > sponsor efforts on a different set of capabilities. Probably=20 > "programmable forwarding of value from > > inputs to outputs", "programmable forwarding of spending conditions fro= m=20 > inputs to outputs" and maybe > > "commit to the exact transaction spending an output" (or more powerful= =20 > introspection). > > > > The lack of a similar enthusiasm for proposals enabling most or all of= =20 > these functionalities (like > > Salvatore Ingala's BIP334 or previously James O'Beirne's and Greg=20 > Sanders' BIP345) suggests such > > loud support are in fact in favour of "just doing something" and=20 > rationalize nice-sounding use cases > > backward from this proposal (but vaults!) because it appears to them to= =20 > be "further down the road". > > I think this view is very dangerous and is part of our motivation for= =20 > redirecting discussions toward > > what these capabilities actually enable. > > > > > it seems somewhat of a loss to not work our way towards really basic= =20 > features for this use-case. > > > > I personally grew more skeptical of the reactive security model of=20 > vaults after working on it. Your > > mileage may vary and that's fine if people want to work on capabilities= =20 > that actually enable vaults, > > but i don't think they should be a required use cases and block=20 > introducing primitives that > > substantially improve existing layer 2s and make new ones possible. > > > > > Indeed, ISTM many use-cases for a construction like TXHASH become a= =20 > lot more substantial with Math > > > [...], I'm quite skeptical that *just* looking at an individual fork= =20 > on its own is the right > > > benchmark. > > > > I agree that modularity and forward composability with potential future= =20 > upgrades are arguments in > > favour of a more flexible approach. But those need to be balanced with= =20 > the additional risk and > > implementation complexity such an approach entails. I'm happy to be=20 > convinced if supporters of this > > approach demonstrate the added flexibility does enable important use=20 > cases and the risks associated > > are manageable. But if nobody is interested in doing so, i don't think= =20 > it's reasonable to hold off a > > safer upgrade as long as it is demonstrated to provide substantial=20 > benefits. > > > > It's also unclear that we should stop at "programmable introspection" i= n=20 > this case. Why not also > > include "programmable amount / spending condition forwarding" too, whic= h=20 > would give you vaults? Why > > not even CAT, which is a neat tool in many situations and would let ZK= =20 > people experiment with > > validation rollups? And at this point, it would seem wiser to just work= =20 > on a sane Bitcoin Script > > replacement rather than throwing buckets of opcodes at it and hoping it= =20 > holds off. Which as we say > > in OP i don't think is realistic. > > > > > I don't see how this results in a net reduction in risk to Bitcoin,= =20 > rather just means more total > > > work and more cruft in Bitcoin's consensus. > > > > In theory, i agree. But by this token the same goes for every future=20 > extension that introduces more > > expressivity to Bitcoin Script. This ties back to the stopping point:= =20 > why add more cruft to the > > existing interpreter when we could all focus on BTCLisp instead? > > > > It's also the case that even if future extensions introduce a superset= =20 > of the capabilities being > > discussed, it's unlikely that such simple ones like "just commit to the= =20 > next transaction" and > > "verify a signature for an arbitrary message" would ever be made fully= =20 > redundant. > > > > Finally, when considering technical debt we should also weigh the actua= l=20 > cost of the implementation > > of these simple capabilities. Signature verification on arbitrary=20 > message reuses existing signature > > checking logic. Similarly, committing to the next transaction can=20 > heavily lean on existing Taproot > > signature messages, only minimally departing when necessary, and be=20 > implemented in a strictly > > simpler manner than the existing CTV proposal. A minimal implementation= =20 > of these capabilities would > > not introduce significant technical debt. > > > > Interestingly, this argument applies more to introducing more involved= =20 > capabilities like arbitrary > > transaction introspection, because of the substantially larger technica= l=20 > debt it would impose to > > first support in Bitcoin Script instead of focusing on a replacement=20 > with transaction introspection > > from the get go. > > > > > Indeed, more flexible introspection provides for a difference in risk= =20 > to the system (though its > > > worth noting we cannot both argue that there is no "demonstrated=20 > utility" *and* that the utility > > > of a change is so substantially higher that it adds material risk to= =20 > the system in the form of > > > MEVil from its use-cases). > > > > Yes we can? It's reasonable to see how arbitrary introspection could be= =20 > useful in various handwavy > > ways, and therefore how they can be used for undesirable applications,= =20 > while also not having an > > important use case it enables clearly defined, much less demonstrated. > > > > > However, given the uses of the Bitcoin chain today, it seems entirely= =20 > possible (assuming > > > sufficient adoption) that we end up with a substantial MEVil risk wit= h=20 > or without any > > > functionality expansion. > > > > Sure, but I=E2=80=99d argue that the presence of risk now is a reason t= o be more=20 > cautious about adding to > > it, rather than accepting it as inevitable. > > > > Best, > > Antoine > > > > > > On Tuesday, June 24th, 2025 at 12:00 PM, Matt Corallo < > lf-l...@mattcorallo.com> wrote: > > > > > > > > > > > Thanks, responding to one specific point: > > > > > > On 6/23/25 9:14 AM, 'Antoine Poinsot' via Bitcoin Development Mailing= =20 > List wrote: > > > > > > > Yet another alternative is a set of more powerful capabilities,=20 > enabling the use cases that "commit to next transaction" > > > > and "verify a BIP340 signature for an arbitrary message" enable and= =20 > more. For instance replacing "commit to the exact > > > > transaction which must spend this output" with "programmable=20 > introspection on the spending transaction's fields" has > > > > been considered. However this approach increases implementation=20 > complexity and broadens the risk surface[^8] > > > > > > > > > Responded to below [1] > > > > > > > which > > > > warrants a compelling demonstration that arbitrary transaction=20 > introspection does enable important use cases not > > > > achievable with more minimal capabilities. > > > > > > > > > I'm somewhat skeptical that showing this isn't rather simple, though = I=20 > admit I've spent less time > > > thinking about these concepts. ISTM even something as simple as a=20 > rate-limit requires more > > > full-featured introspection than only "commit to the exact next=20 > transaction" can provide. For > > > example, a trivial construction would be something which requires tha= t=20 > transactions spending an > > > output have an output which claims at least Amount - Rate, which=20 > requires both more full-featured > > > introspection as well as a bit of math. Given one of the loudest=20 > groups advocating for the > > > additional features of CTV+CSFS are enterprise or large-value persona= l=20 > custody providers, it seems > > > somewhat of a loss to not work our way towards really basic features= =20 > for this use-case. > > > > > > More generally, more full-featured introspection like TXHASH provides= =20 > a lot of flexibility in the > > > constructs people can build. For example, allowing BYO fees in the=20 > form of an additional input + > > > output in a transaction, rather than fixing an anchor output in the= =20 > fixed "next transaction" > > > commitment to allow for fees (and then requiring the same additional= =20 > input + output later). There's > > > also open questions as to the incentive-compatibility of anchors in a= =20 > world with expensive block > > > space, as OOB fees become much cheaper. > > > > > > Indeed, ISTM many use-cases for a construction like TXHASH become a= =20 > lot more substantial with Math > > > (though, again, I spend less time thinking about the use-cases of=20 > these things than most, so I'm > > > sure others have more examples), I'm quite skeptical that just lookin= g=20 > at an individual fork on > > > its own is the right benchmark. Sure, functionality in proposed=20 > changes to Bitcoin's consensus need > > > to be well-justified, but they don't need to be well-justified purely= =20 > on their own. We add things > > > like OP_SUCCESS opcodes in soft forks specifically to expand the set= =20 > of things we can do later, not > > > specifically in this fork. > > > > > > If we assume that we end up wanting things like velocity limits (whic= h=20 > I imagine we would?) then it > > > seems to me we should do a logical fork that adds features today, but= =20 > which will allow us to make > > > minimal extensions in the future to further expand its use-cases=20 > later. Taking a more myopic view of > > > the present and ignoring the future results in us doing one thing=20 > today, then effectively replacing > > > it later by adding more flexibility in a new opcode later, subsuming= =20 > the features of what we do > > > today. I don't see how this results in a net reduction in risk to=20 > Bitcoin, rather just means more > > > total work and more cruft in Bitcoin's consensus. > > > > > > [1] > > > > > > Responding to the MEVil question OOO because I think the above should= =20 > go first :). > > > > > > Indeed, more flexible introspection provides for a difference in risk= =20 > to the system (though its > > > worth noting we cannot both argue that there is no "demonstrated=20 > utility" and that the utility of > > > a change is so substantially higher that it adds material risk to the= =20 > system in the form of MEVil > > > from its use-cases). However, given the uses of the Bitcoin chain=20 > today, it seems entirely possible > > > (assuming sufficient adoption) that we end up with a substantial MEVi= l=20 > risk with or without any > > > functionality expansion. This mandates a response from the Bitcoin=20 > development community in either > > > case, and I'm confident that response can happen faster than any=20 > reasonable soft fork timeline. > > > > > > While its possible that existing CSV-based MEVil risk never grows=20 > beyond its current anemic state > > > (due to preferences for stronger trust models from their users), and= =20 > that there's a particularly > > > clever design using expanded introspection that improves the trust=20 > model such that suddenly > > > CSV-based protocol use explodes, ISTM given the risk and the need to= =20 > mitigate it on its own, taking > > > decisions that are sub-optimal for Bitcoin's consensus on this basis= =20 > isn't accomplishing much and > > > has real costs. > > > > > > Matt > > > > > > -- > > > You received this message because you are subscribed to the Google=20 > Groups "Bitcoin Development Mailing List" group. > > > To unsubscribe from this group and stop receiving emails from it, sen= d=20 > an email to bitcoindev+...@googlegroups.com. > > > To view this discussion visit=20 > https://groups.google.com/d/msgid/bitcoindev/8a9a2299-ab4b-45a4-8b9d-9579= 8e6bb62a%40mattcorallo.com > . > > > > -- > > You received this message because you are subscribed to the Google=20 > Groups "Bitcoin Development Mailing List" group. > > To unsubscribe from this group and stop receiving emails from it, send= =20 > an email to bitcoindev+...@googlegroups.com. > > To view this discussion visit=20 > https://groups.google.com/d/msgid/bitcoindev/73PXNVcmgiN2Kba63P2SRZfs42lv= gME_8EF-DlYtkOSY8mLRxEXPEw5JAi5wtPU2MEMw1C6_EDFHKKrhaa1F53OgIJOcam-kbOUP3aG= 2_e0%3D%40protonmail.com > . > --=20 You received this message because you are subscribed to the Google Groups "= Bitcoin Development Mailing List" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to bitcoindev+unsubscribe@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/= 88d14bbe-484c-4d12-a3e5-f894b17f5c64n%40googlegroups.com. ------=_Part_3299_2005966468.1750953760462 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable > The ability to commit to the exact transaction spending an output is u= seful to reduce interactivity in second-layer
protocols.

Where do you stand on explicit commitments to neighbor prevouts? My= understanding is that this capability would be extremely useful, for BitVM= and for making offers to buy UTXOs. If the goal is to commit to the "exact= transaction spending an output," CTV alone wouldn't quite get you there.
On We= dnesday, June 25, 2025 at 5:28:02=E2=80=AFPM UTC-4 Ethan Heilman wrote:
> Why not ev= en CAT, which is a neat tool in many situations and would let ZK people exp= eriment with validation rollups? And at this point, it would seem wiser to = just work on a sane Bitcoin Script replacement rather than throwing buckets= of opcodes at it and hoping it holds off.

A Bitcoin Script replacement is likely to be a lot of work and many of
the features will be informed by what people are building at the time
it is designed. Merging a low implementation complexity opcode like
OP_CAT (BIP-347) would provide useful data to inform a Bitcoin Script
replacement.

In addition to allowing ZK people to experiment, OP_CAT also has many
simple use cases that improve everyday boring tapscripts.

> Sure, but I=E2=80=99d argue that the presence of risk now is a rea= son to be more cautious about adding to it, rather than accepting it as ine= vitable.

Addressing MEVil, if addressing MEVil is considered an important goal,
requires being proactive and enabling the ability to build better
protocols on Bitcoin. This is because, all things being equal,
building a protocol that doesn't care about MEVil resistance is eas= ier
and requires less scripting functionality than one that does.

On Wed, Jun 25, 2025 at 12:54=E2=80=AFPM 'Antoine Poinsot' via = Bitcoin
Development Mailing List <bitco...@googlegroups.com> wrote:
>
> Thanks for sharing some objections. Here is my attempt at addressi= ng them.
>
> > ISTM even something as simple as a rate-limit requires more f= ull-featured introspection than only
> > "commit to the exact next transaction" can provide.= For example, a trivial construction would be
> > something which requires that transactions spending an output= have an output which claims at least
> > Amount - Rate, which requires both more full-featured introsp= ection as well as a bit of math.
>
> Yes. These capabilities are really only useful for reducing intera= ctivity in second-layer protocols.
> They do not (reasonably) help for vaults and we do not claim it as= a use case.
>
> Previous efforts to promote opcodes implementing those capabilitie= s have unfortunately fallen into
> the trap of overpromising and claiming use cases they do not reall= y enable. But this should not make
> us overlook what they are really good at: interactivity reduction.
>
> Do you think that the use cases presented in OP, if demonstrated, = are not enough to warrant soft
> forking in a primitive enabling them?
>
> > Given one of the loudest groups advocating for the additional= features of CTV+CSFS are enterprise
> > or large-value personal custody providers
>
> Yes. We intentionally do not mention vaults as a use case in our s= teelman. We should not change
> Bitcoin on the basis of misleading use cases. If people are intere= sted in vaults, they should
> sponsor efforts on a different set of capabilities. Probably "= ;programmable forwarding of value from
> inputs to outputs", "programmable forwarding of spending= conditions from inputs to outputs" and maybe
> "commit to the exact transaction spending an output" (or= more powerful introspection).
>
> The lack of a similar enthusiasm for proposals enabling most or al= l of these functionalities (like
> Salvatore Ingala's BIP334 or previously James O'Beirne'= ;s and Greg Sanders' BIP345) suggests such
> loud support are in fact in favour of "just doing something&q= uot; and rationalize nice-sounding use cases
> backward from this proposal (but vaults!) because it appears to th= em to be "further down the road".
> I think this view is very dangerous and is part of our motivation = for redirecting discussions toward
> what these capabilities actually enable.
>
> > it seems somewhat of a loss to not work our way towards reall= y basic features for this use-case.
>
> I personally grew more skeptical of the reactive security model of= vaults after working on it. Your
> mileage may vary and that's fine if people want to work on cap= abilities that actually enable vaults,
> but i don't think they should be a required use cases and bloc= k introducing primitives that
> substantially improve existing layer 2s and make new ones possible= .
>
> > Indeed, ISTM many use-cases for a construction like TXHASH be= come a lot more substantial with Math
> > [...], I'm quite skeptical that *just* looking at an indi= vidual fork on its own is the right
> > benchmark.
>
> I agree that modularity and forward composability with potential f= uture upgrades are arguments in
> favour of a more flexible approach. But those need to be balanced = with the additional risk and
> implementation complexity such an approach entails. I'm happy = to be convinced if supporters of this
> approach demonstrate the added flexibility does enable important u= se cases and the risks associated
> are manageable. But if nobody is interested in doing so, i don'= ;t think it's reasonable to hold off a
> safer upgrade as long as it is demonstrated to provide substantial= benefits.
>
> It's also unclear that we should stop at "programmable in= trospection" in this case. Why not also
> include "programmable amount / spending condition forwarding&= quot; too, which would give you vaults? Why
> not even CAT, which is a neat tool in many situations and would le= t ZK people experiment with
> validation rollups? And at this point, it would seem wiser to just= work on a sane Bitcoin Script
> replacement rather than throwing buckets of opcodes at it and hopi= ng it holds off. Which as we say
> in OP i don't think is realistic.
>
> > I don't see how this results in a net reduction in risk t= o Bitcoin, rather just means more total
> > work and more cruft in Bitcoin's consensus.
>
> In theory, i agree. But by this token the same goes for every futu= re extension that introduces more
> expressivity to Bitcoin Script. This ties back to the stopping poi= nt: why add more cruft to the
> existing interpreter when we could all focus on BTCLisp instead?
>
> It's also the case that even if future extensions introduce a = superset of the capabilities being
> discussed, it's unlikely that such simple ones like "just= commit to the next transaction" and
> "verify a signature for an arbitrary message" would ever= be made fully redundant.
>
> Finally, when considering technical debt we should also weigh the = actual cost of the implementation
> of these simple capabilities. Signature verification on arbitrary = message reuses existing signature
> checking logic. Similarly, committing to the next transaction can = heavily lean on existing Taproot
> signature messages, only minimally departing when necessary, and b= e implemented in a strictly
> simpler manner than the existing CTV proposal. A minimal implement= ation of these capabilities would
> not introduce significant technical debt.
>
> Interestingly, this argument applies more to introducing more invo= lved capabilities like arbitrary
> transaction introspection, because of the substantially larger tec= hnical debt it would impose to
> first support in Bitcoin Script instead of focusing on a replaceme= nt with transaction introspection
> from the get go.
>
> > Indeed, more flexible introspection provides for a difference= in risk to the system (though its
> > worth noting we cannot both argue that there is no "demo= nstrated utility" *and* that the utility
> > of a change is so substantially higher that it adds material = risk to the system in the form of
> > MEVil from its use-cases).
>
> Yes we can? It's reasonable to see how arbitrary introspection= could be useful in various handwavy
> ways, and therefore how they can be used for undesirable applicati= ons, while also not having an
> important use case it enables clearly defined, much less demonstra= ted.
>
> > However, given the uses of the Bitcoin chain today, it seems = entirely possible (assuming
> > sufficient adoption) that we end up with a substantial MEVil = risk with or without any
> > functionality expansion.
>
> Sure, but I=E2=80=99d argue that the presence of risk now is a rea= son to be more cautious about adding to
> it, rather than accepting it as inevitable.
>
> Best,
> Antoine
>
>
> On Tuesday, June 24th, 2025 at 12:00 PM, Matt Corallo <lf-l...@mattcorallo.com> wrote:
>
> >
> >
> > Thanks, responding to one specific point:
> >
> > On 6/23/25 9:14 AM, 'Antoine Poinsot' via Bitcoin Dev= elopment Mailing List wrote:
> >
> > > Yet another alternative is a set of more powerful capabi= lities, enabling the use cases that "commit to next transaction"
> > > and "verify a BIP340 signature for an arbitrary mes= sage" enable and more. For instance replacing "commit to the exac= t
> > > transaction which must spend this output" with &quo= t;programmable introspection on the spending transaction's fields"= has
> > > been considered. However this approach increases impleme= ntation complexity and broadens the risk surface[^8]
> >
> >
> > Responded to below [1]
> >
> > > which
> > > warrants a compelling demonstration that arbitrary trans= action introspection does enable important use cases not
> > > achievable with more minimal capabilities.
> >
> >
> > I'm somewhat skeptical that showing this isn't rather= simple, though I admit I've spent less time
> > thinking about these concepts. ISTM even something as simple = as a rate-limit requires more
> > full-featured introspection than only "commit to the exa= ct next transaction" can provide. For
> > example, a trivial construction would be something which requ= ires that transactions spending an
> > output have an output which claims at least Amount - Rate, wh= ich requires both more full-featured
> > introspection as well as a bit of math. Given one of the loud= est groups advocating for the
> > additional features of CTV+CSFS are enterprise or large-value= personal custody providers, it seems
> > somewhat of a loss to not work our way towards really basic f= eatures for this use-case.
> >
> > More generally, more full-featured introspection like TXHASH = provides a lot of flexibility in the
> > constructs people can build. For example, allowing BYO fees i= n the form of an additional input +
> > output in a transaction, rather than fixing an anchor output = in the fixed "next transaction"
> > commitment to allow for fees (and then requiring the same add= itional input + output later). There's
> > also open questions as to the incentive-compatibility of anch= ors in a world with expensive block
> > space, as OOB fees become much cheaper.
> >
> > Indeed, ISTM many use-cases for a construction like TXHASH be= come a lot more substantial with Math
> > (though, again, I spend less time thinking about the use-case= s of these things than most, so I'm
> > sure others have more examples), I'm quite skeptical that= just looking at an individual fork on
> > its own is the right benchmark. Sure, functionality in propos= ed changes to Bitcoin's consensus need
> > to be well-justified, but they don't need to be well-just= ified purely on their own. We add things
> > like OP_SUCCESS opcodes in soft forks specifically to expand = the set of things we can do later, not
> > specifically in this fork.
> >
> > If we assume that we end up wanting things like velocity limi= ts (which I imagine we would?) then it
> > seems to me we should do a logical fork that adds features to= day, but which will allow us to make
> > minimal extensions in the future to further expand its use-ca= ses later. Taking a more myopic view of
> > the present and ignoring the future results in us doing one t= hing today, then effectively replacing
> > it later by adding more flexibility in a new opcode later, su= bsuming the features of what we do
> > today. I don't see how this results in a net reduction in= risk to Bitcoin, rather just means more
> > total work and more cruft in Bitcoin's consensus.
> >
> > [1]
> >
> > Responding to the MEVil question OOO because I think the abov= e should go first :).
> >
> > Indeed, more flexible introspection provides for a difference= in risk to the system (though its
> > worth noting we cannot both argue that there is no "demo= nstrated utility" and that the utility of
> > a change is so substantially higher that it adds material ris= k to the system in the form of MEVil
> > from its use-cases). However, given the uses of the Bitcoin c= hain today, it seems entirely possible
> > (assuming sufficient adoption) that we end up with a substant= ial MEVil risk with or without any
> > functionality expansion. This mandates a response from the Bi= tcoin development community in either
> > case, and I'm confident that response can happen faster t= han any reasonable soft fork timeline.
> >
> > While its possible that existing CSV-based MEVil risk never g= rows beyond its current anemic state
> > (due to preferences for stronger trust models from their user= s), and that there's a particularly
> > clever design using expanded introspection that improves the = trust model such that suddenly
> > CSV-based protocol use explodes, ISTM given the risk and the = need to mitigate it on its own, taking
> > decisions that are sub-optimal for Bitcoin's consensus on= this basis isn't accomplishing much and
> > has real costs.
> >
> > Matt
> >
> > --
> > You received this message because you are subscribed to the G= oogle Groups "Bitcoin Development Mailing List" group.
> > To unsubscribe from this group and stop receiving emails from= it, send an email to bitcoindev= +...@googlegroups.com.
> > To view this discussion visit http= s://groups.google.com/d/msgid/bitcoindev/8a9a2299-ab4b-45a4-8b9d-95798e6bb6= 2a%40mattcorallo.com.
>
> --
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> To unsubscribe from this group and stop receiving emails from it, = send an email to bitcoindev+...@= googlegroups.com.
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