Having a discussion with someone privately about why proof-of-burn is incompatible with a hard fork upgrade and I thought I would share:
Proof of burn for an upgrade is fundamentally unfair. What if you owned the coin and were not checking in on the forums for a couple of months? Then you would not receive your stake in the upgraded chain? That would be so wrong! And if the "burn" was only to vote for or against consensus then nobody would do it because then there would be a chance that the vote fails in which case you just burned all your stake (!). As you can see, proof-of-burn is not a substitute for blockchain voting, is fundamentally unfair for hard forking, and does not work for proving or achieving consensus on a community decision. It is useful as a distribution mechanism for a new asset, but not for this purpose.
Just a tangent really, but I think it may lay to rest some issues for those who brought it up.