'Sean McDermott’s cast now is the third head coaching regime in the last five years. (We’re not counting interims.) Just look at the defensive scheme changes since Chan Gailey took over in 2010. The defense has gone from the 3-4 (George Edwards) to the 4-3 (Dave Wannstedt) to the 3-4 (Mike Pettine) to the 4-3 (Jim Schwartz) to the 3-4 (Dennis Thurman) to the 4-3 (Leslie Frazier).'