After Tampa won the Super Bowl in 2002 and Indianapolis and Chicago played for the Super Bowl in 2006, there was a swing of teams playing the "Tampa 2" style defense, with penetrating defensive linemen and small, fast linebackers. Tampa, Indianapolis, Chicago, Buffalo, Detroit and St. Louis all were playing a version of Tony Dungy's scheme. Now all of them but Indianapolis and Chicago have veered away from the defense. Here's a line from a Mike Lombardi column on the National Football Post regarding Chicago's defensive woes: "No one in the NFL who tries to run a steady diet of the Tampa 2 schemes will survive. Nor will building the team in the style and manner of the old Bucs -- that was one-time success story.
In fact, the Bears don’t run Tampa 2 as much as they have in the past, but they lack complexity with their defense. So once teams handle their three or four pressure packages, it’s not hard to make big plays."
Regardless of how much trouble the Bills might or might not have in adjusting to the 3-4 scheme, it became obvious the last several years that the Bills D was a bad matchup in the physical AFC East. Indy has been able to thrive with it because the Colts' edge pass rushers are so great, and - more importantly - the Colts have had such a huge advantage over their division foes at the quarterback position.