Thank you so much for all the advice. It is still a hard decision. He does seem uncomfortable as he shakes his head as if bothered by something, but as some of you have pointed out I do not know how he experiences all of this.
It is interesting to see what a hot issue this is for all of us and this explains why my decision is so hard.
I could guess that combs and wattles help with temperature regulation in the summer, even if they do not sweat. They can circulate blood through this uncovered flesh and cool themselves, the same way African elephants cool themselves with their ears. In Massachusetts hot summers are starting to be runners up to cold winters for chicken stressors, but even at that Fergus' wattle is ginormous and the hens survive without anything like that. I dunno that he really needs it. Cutting it off would also be traumatic, the narrowest and thinnest point is more than an inch long and kind of thick. He is seriously blessed in the wattle department.
The frost damage is worse than it looked on the pics. The wattle was covered in salve and reflected alot. Some of it has turned white since this a.m. I think it is still worth waiting to see how it turns out. I am not a cruel person but I would like to keep chix for a long time and want to keep learning about them. I have had birds lose the tips of combs when they blackened and feel off after frostbite that started out with this kind of purpling. It is hard to imagine chunks of this enormous massive wattle doing that. I think this discussion is unresolved enough that if I can I will post pics of the progression so others can see how this turns out.
From a future perspective, I have to say that this has made me realize that his wattle and really cold temps are not a good match. I don't want to have him live inside in cold weather, and I don't want him to suffer if I can prevent it. I am failry certain this injury is painful, if I watch him I can see it in his behavior, and it looks like it hurts. So in some ways I am not sure if I lack information or will power. After all this is over I at least will have more information, and will share it. -- mj