...I think at times he put together really good game plans designed to catch an opponent off-guard and keep them off balance. Problem was, he too often didn't like to scheme for individual teams and instead (according to his own words) liked to treat every team the same and didn't do individual game plans for specific teams.
Defensive game plans of his that really stand out in my mind that show his brilliance was the 2008 UCLA game, the 2009 Oklahoma game and most of the 2012 season (it was a lot more fun watching our defense in 2012 than it was watching our offense).
Most times though, he seemed to be content with the status quo and doing the same ol' same ol'. Play the battle for field position game, punt when your drive stalls at the opponents 30 yd line, keep people in front and try not to give up big plays, etc.