I seriously wonder if Gregg puts our Defense into a base set to start each game, simply to see what the other team's Offense will do. After we watch them throw a heymaker, and our Offense responds, he tightens up a bit.
By the second half, the opposing Offense is usually in catch-up mode, so the D starts to tighten. It's almost like a snake constricting around its prey.
After this many games since he joined the staff, I don't even blink when a team jumps out with early scores. It seems like it's just all part of the plan.