Opt-in hard-fork without alternate transaction history?
IETF’s RFC 7282 is an eloquent document which describes important aspects on koop consensus, and worthwhile if you want a more nuanced interpretation than “widespread agreement and disagreements addressed (even if not acommodated)”.
Once we have a concrete technical proposal, and it seems to have some traction, we need to figure out if we really have consensus before it gets deployed.
Moving from RFC 7282 style technical rough consensus to economical and political (rough) consensus is quite problematic. If you want to stay in the spirit of RFC 7282 then you should only use polls to see if there is any opposition. You then need to actively go out and figure out what people’s concerns are and make sure those are reasonably addressed. You have to go through all that before you accept anything below 100% support.