On Feb 22, 2021, at 05:16, Anthony Towns <aj@erisian.com.au> wrote:

If a lockinontimeout=true node is requesting compact blocks from a
lockinontimeout=false node during a chainsplit in the MUST_SIGNAL phase,
I think that could result in a ban.

More importantly, nodes on both sides of the fork need to find each other.

(If there was going to be an ongoing fork there'd be bigger things to
worry about...)

I think it should be clear that a UASF-style command line option to allow consensus rule changes in the node in the short term, immediately before a fork carries some risk of a fork, even if I agree it may not persist over months. We can’t simply ignore that.

I think the important specific case of this is something like "if a chain
where taproot is impossible to activate is temporarily the most work,
miners with lockinontimeout=true need to be well connected so they don't
end up competing with each other while they're catching back up".

Between this and your above point, I think we probably agree - there is material  technical complexity hiding behind a “change the consensus rules“ option. Given it’s not a critical feature by any means, putting resources into fixing these issues probably isn’t worth it.

Matt