Man, I hope this turns out to be true--for all the reasons you give, Zooker, plus one more practical and specific one: as I have stated before, although we all know that CHOMP himself is a superb defensive-mind, an innovator who is on the cutting edge of aggressively defensive GAME-planning, as the Head Coach, ideally he'd be well-served with a separate DC who is "on the same page" with him as far as that philosophy and the places one can go with it, who speaks the same language, someone he can trust to know what needs to be done and gets to work doing it, while CHOMP himself can focus on the bigger-picture issues and problems, the responsibilities of running the program and attending to the needs of his players as well--until it's game-week and hopefully everything is ready for him to "plug back in", get involved once more in the specifics of his "D".
"Head Coach" is a whole different deal from "Coordinator", ESPECIALLY at one of the handful of "Elite Programs"--Charlie Weis would no doubt have a lot to share on this subject, were he so inclined. I'm not saying Coach Muschamp CAN'T do both, just that from everything I understand and have observed in other people and programs, being able to delegate the bulk of the details in your specialty to a close, like-minded friend and colleague really is the ideal situation.