Gammadoodler
Hero
Are all Earth humans 7ft tall and play pro basketball in the NBA? Are all of them able to powerlift at exactly equal ability? Are all of them able to become kung fu masters and break stacks of concrete with their limbs and head?It can't be physiological since if it was, all biological creatures of the same type would do it. That can be true if we're willing to entertain fighter as having a specific origin (akin to how sorcerers get their spells) but the point is we're not. It has to come from something external (a supernatural effect) or it has to be something completely natural (and that gets us back to what mundane limits are).
Bear in mind, I don't have it out for just fighters. Rogues are equally guilty of having reality-bending powers and barbarians are barely squeaking in depending on how supernatural you view rage. I'd like to see all those classes be better defined or i'd like to see magic taken down a peg or three. But they tried the latter and it failed, so the only hope is to give martial's the toys needed to hang.
Of course not. And that's plain old Earth human differences.
Who's to say what differences might exist for fantasy folk in a fantasy setting?