[bitcoin-dev] OP_CODESEPARATOR Re: BIP Proposal: The Great Consensus Cleanup

[Matt Corallo]

Note that even your carve-outs for OP_NOP is not sufficient here - if you were using nSequence to tag different pre-signed transactions into categories (roughly as you suggest people may want to do with extra sighash bits) then their transactions could very easily have become un-realistically-spendable. The whole point of soft forks is that we invalidate otherwise-unused bits of the protocol. This does not seem inconsistent with the proposal here.

> On Mar 9, 2019, at 13:29, Russell O'Connor <roconnor at blockstream.io> wrote:
> Bitcoin has *never* made a soft-fork, since the time of Satoishi, that invalidated transactions that send secured inputs to secured outputs (excluding uses of OP_NOP1-OP_NOP10).