I like where he says, "A physical defense is one that is flying to the football, and the opponent is going backwards and not falling forward."
This game is about field position, and every inch counts. I hate to see our defense come up to make the tackle and not push the RB or WR backwards. The offense wiggles or pushes for the extra yardage.
It is an attitude to stop them in their tracks and push them backwards every play.
You are battling for every inch of field position.
It seems he teaches and preaches that attitude on defense.