Watch the reruns of the games. There'd be ball carriers and receivers consistently running with no one within five yards of them. You can say the defense was out of position once in a while, but as often as it happened you've gotta say the players were assigned to be in the wrong position. Oh yeah, whose job was it to teach tackling? Even pros need to learn, to be taught and need to practice their skills. If they didn't then the teams wouldn't need to hire coaches in the first place. When coaches see something as being deficient, it's their job to work on it with their players. As far as Spags' system working, he was a DC for exactly two years inheriting a very well coached group of players including a stellar defensive line. He was the one that was exposed, inheriting an average group of defensive players that he couldn't coach to play average. And average was all we really needed.