I'm curious why. I guess I just dont understand why, if one person can do something (ali) another one can't do the same thing.
It's called genetic diversity- everybody is different. Environment plays a large part too.
Seriously, though... I think it's a bit foolish to assume that a "proper" martial artist can automatically punch more efficiently (struggling for a term there) than a boxer. There's an assumption there that boxers are comparitively unskilled at punching. This is silly, and you're not talking about an "ordinary" boxer either. Ali was seriously tough and seriously skilled and seriously heavier than Bruce Lee. He wasn't just a big guy- he knew how to throw a punch.
I'm sure there was more going through your mind than you put there.... I mean, by that rationale why are we learning Aikido when we could go create our own martial art? What's wrong with all those shihan?