This would be the reason. Iowa is a GREAT job. The pay would be fantastic, the fan base are rabid, the boosters are generous, and they will soon have the best facilities in the world. But... why would DT want that? He is living what appears to be a pretty good life at the moment, without the headaches that come from dealing with a few dozen 18-24 year olds. (And there is no indication that he even has the "wiring" necessary to be a head coach)