The suggestion by Mark Friedenbach, Blockstream Co-Founder and Bitcoin Core Developer, wasnt to just simply blacklist coins
it was to reorg the hack away entirely. Of course he backtracked quickly when his Blockstream coworkers and other Core contributors squealed loudly about it.
Zane, this is many times larger than the block reward for the duration of time that has elapsed. Have you considered getting a list of transactions to blacklist and getting miners to reorg the theft? The window of time for that hasn't closed.
(If this happened in the last day, then that's 12.5*144 blocks = 1,800 BTC in subsidy. That's <2% of the hack.)
https://www.reddit.com/r/Bitcoin/comments/4vupa6/p2shinfo_shows_movement_out_of_multisig_wallets/d61qyajThe only people who could damage fungibility at this point are the Core developers and the handful of dominant mining pool ops. These are the parties to whom you should be directing your plea. Directing the attacker to do what you say reads like a letter to santa.