michael bennett and cliff avril suggest you are wrong. both fairly average starting DEs previously became back ups who played 50% of the snaps yet provided more than double previous pressures/sacks per pass rush. you need players in both spots: DL and DB. you can account for a good rusher fairly easily. very hard to account for a good overall DL. but how you do that is to pass very quickly. if DB can't cover 3 step drops the DL is helpless. you can likewise account for a good coverage players. very hard to account for a good overall secondary. way to do that is to run the ball and attack the LBs with TE/RB. dallas was not good enough in any area of the defense in 2013. seattle was good enough plus some in all 3 areas. the ratings weren't flukes they represented the talent levels on the field.