On the second point, Gsp doesn't have the best chin on the WW division either. That doesn't change the fact that he is the greatest WW of all time. Hey, just like Cain is the best HW in the world. Just saying it, not screaming it.
Oh, and if a B HW like Kharitonov can KO the fuque out the Reem, I'm going to say that the second best HW in the world can do the same.