...in most inferences it could even denote an aspect of exceeding expectations. The Urban Dictionary says this: "When someone does something really well."

Playing insane to most people I think means they played "out of their minds", I think most people would think that a passer rating in the 150-170 range is killing it but likely not "insane". I certainly haven't read any posts on CB where posters described Hall or Romney's playing as "insane" or any inference of that nature.

I can't help it if you add meaning that wasn't there in the discussion.