I know, I suppose I just have the idealism that the 'pinnacle' of human potential is to go past our limits. At some point you have to cross a fine line between peak human, and transhuman when you think like that. Like I said, for me 'peak' would be whatever physical perfection we can find, to the point that the only way we could improve from there is to exist as something other than physical. But I don't really want to argue interpretations of 'peak', so I'll just concede that I'm a bit crazy.
I already kind of consider Cap to be above human, at least marginally, since for all we know, we're not genetically predisposed to handle all those physical specializations at once. I mean in a way that goes beyond determination. Like is a normal human's metabolism capable of keeping up with such a perfectly honed body? For instance, spider's can only grow as much as the oxygen levels in their environment allow, due to a 'flaw' in their biological design. Stuff like that needs to be surpassed, not just worked around. Not to mention Steve cannot get drunk and if he's anything like Blonsky, can make a full recovery in just a few weeks after having the majority of his skeleton wrecked. There's some weird biology going on there, it's just not super obvious like an 8 foot tall green monster.
How is this all explained as possible? The Super Soldier Serum. It does more than unlock the potential. It expands the potential. It's what allowed Steve to be all these things, and is already an outside force that drastically alters things. No matter how much a human trains, they'll never be able to make the kind of recovery Blonsky did. So what's a bit of gamma radiation on top of that? I just think of gamma as being something that kicked whatever variant of the serum Banner injected himself with, up to 11.