Guess I better be prepared just in case.....yuck. I've been told blistering is pretty normal, and one person said he just pops the blister to speed things up.
It seems there is as wide a range on handling/responding to blackened combs and wattles as can be - from do abolutely nothing to daily nursing care. I want to do the least in hopes of causing the least harm and letting the body do its thing. But, I don't want to cross that line into neglect either!
Let me qualify my comment it is coming purely from a human treatment response, I have never treated rooster combs for frostbite.