lost on players who aren't physically or mentally capable of executing it.
Effective defenses can be assimilated quickly. The current best case in point is the Falcons. Their yardage allowed per game (343.1, 15th in the league) isn't a whole lot better than Buffalo's 369.7 (20th). But only three NFL teams have given up fewer points than Atlanta has this season.
The architect of that defense is Wade Phillips. In his first season there, he introduced a 3-4 defense that has renovated a Falcons defense that was one of the league's worst last year. He has done it with players such as John Holecek, Sam Rogers and Keion Carpenter, who helped Phillips have successful defenses with the Bills.
This is the same Wade Phillips who was all but run out of Buffalo on a rail, and replaced with Gregg Williams. Think Phillips might be having more defensive success, and overall success, than Williams has? Consider this: In his 28 games as Bills coach, Williams has lost 19. That's as many as Phillips lost, but it took him 48 regular-season games to do that.
It shouldn't surprise us that Phillips had quick success. In 1997, as defensive coordinator, he turned around the Bills' defense in less than a week. When inside linebackers Chris Spielman and the late Damien Covington both were injured at the same time, Phillips went away from his preferred 3-4 to a 4-3 defense.
On the other hand, Williams seems to be prepared to ride his 46 mutant all the way to the unemployment line.