The bacchanal over Number Four's return has spread through the sports-writing world at ludicrous speed1 as has the dissolution of decades-long hatred among Vikings fans toward the former Cheesehead - hypocrites, the lot of you - but thus far I haven't come across a story that discusses regression toward the mean, which could be a factor in the upcoming NFL season.
In his book The Drunkard's Walk, Leonard Mlodinow describes the regression toward the mean: any series of random events an extraordinary event is most likely to be followed, due purely to chance, by a more ordinary one. For example, take baseball (for Hank). In 1961, New York Yankee right fielder Roger Maris broke Babe Ruth's single-season home run record (which had sat at 60 for 34 years) by slugging 61 homers. At first glance, not knowing anything about Maris, you'd assume he was consistently hitting home runs throughout his career, as anyone who achieved that level of success would have to be pretty good at hitting home runs, right? Wrong.2 He hit a total of 275 home runs over 12 seasons for an average of 23 per year. In that time, Maris hit 30+ home runs only three times (1960-1962 seasons). In 1962 he hit 33 home runs, 28 fewer than the previous year. Maris' extraordinary year, breaking Babe Ruth's record, was followed by a more ordinary year - his season home run total regressed back toward the mean.
Now, a professional athlete's skill will likely increase as he/she practices, learns new skills, gains strength, etc. Then, as the body ages, the skill level will taper off again. Even the Great One, Wayne Gretzky, is not immune from the laws of statistics - arguably the best hockey player ever, he started slowing down in his later years. But these gains and losses will be incremental and not as shocking as, say, the Minnesota Twins going from the basement of the American League in 1990 (and one of the worst in all of baseball) to winning the World Series in 1991.
This brings me back to Favre.3 He'll go to the Hall of Fame, no doubt about it. He had easily one of his best seasons ever last year, if not his best. His 2009 passer rating (a measure of quarterback performance) shattered his previous season records.4 So, if you've been following along with me, it stands to reason that his season of Purple Power this year will regress toward the mean, and he'll perform, at least statistically, at a lower level than he did last year.5 The Vikes had a great team last year and some standout players (and a really douche coach), and if it wasn't for that pesky interception Favre threw in the final two minutes of the fourth quarter in the NFC Championship game against the saints, they may have gone to the Superbowl. Given that this is Favre's "last season" so there will be emotional inspiration, and the roster from last year's great team remains basically unchanged, you could ostensibly presume that they'll do pretty well again. But will Favre have the winning season he is hoping for, or will he regress toward the mean and finish his 20th season without that final feather in his Helga Hat? Will statistics prevail? Come late January, we'll find out...
1 Colonel Sandurz: "Light speed, too slow?" Dark Helmet: "Yes, we're gonna have to go right to ludicrous speed."
2 This is not to say that Roger Maris was not a great ballplayer. He was. Some consider him to still be the legitimate home-run record holder given that those who came after him were accused of being on steroids. Anyway, he was a great player, but he wasn't a guy who hit 40 or 50 homers every year.
3 Caveat: I don't like him. Yes, he can play football. But he couldn't make a decision and stick with it if his life depended on him. He's "retired" so many times Social Security must have whiplash. And what makes you so %&$#@ special that you don't have to go to training camp? If Lindsay Lohan can hang out with criminals and thugs, so can you.
4 NFL passer rating takes into account Completion Percentage, Average Yards Per Attempt, Percentage of Touchdown Passes, and Percentage of Interceptions.
5 A mean of "awesome" still isn't bad.