Say the league average on 4th down conversions is 1 in 3, which I believe is close to the actual rate. Let's imagine the Bills, for whatever reason, are much better. Their mean is 1 in 6 let's say for 2009. That's the mean they are going to regress to, not the league average. The league average has nothing to do with individual team cases. Know I'm preaching to the choir here but I can't stand the other guy.