There are other concerns in cooking besides protein, do you have information about stuff like damage to vitamins or antioxidant compounds? This might be more of a concern with plants than meat, I'm not sure.
Rancidity is one issue that comes to mind, like why it's okay to cook saturated fats or even monounsaturated like olive oil, but to avoid cooking polys like flax since they go rancid under heat easier, something like that.
Which brings to mind the question: there's this big hard-on for grass-fed beef because it's apparently higher in omega 3 than corn-fed beef or something like that. But if we're going to be cooking the meat, is having polyunsaturated animal fat necessarily a good thing? I could understand if we were eating the meat raw, but perhaps if we're going to be cooking the meat, we should have the saturated corn fat and just cut as much of it off as possible.
I mean seriously, no matter how Omega3 grassy beef is, surely we'd be better off relying on uncooked sources, like cold-pressed flax or fish oils.