I fucking hate to say this but some could argue that fatties have more "stamina" in bed.. IE maintain a boner. The rationale is that fit people come sooner because they are healthy while a fatty slows down thier pump and thrust so as not to have a coronary event. Of course this is NOT strictly true because a human can just slow down because they wish to rather than have to. But then fattys won't point that out in an argument...