I guess what many of these young, very stupid folks who select the "Top QB's List" forget is when Moon, Aikman, Bradshaw, and Elway played, they got the absolute hell beaten out of them. There were no QB protection rules that the new young guns are protected by. I think it's unfair to group these players from different eras onto the same list. Aikman suffered at least eight concussions, at least two in a single season, a season he can't remember. Today, the QB's have protection rules and protocols that were not present when these four greats played. If you don't think that makes a huge difference in completion percentages, you've never played football!