MuLLLen hardly was competing for the division. In a post above, an Bama fan lays out the one year that everyone overreacted and how they came tumbling down. And, Gator fans will not take your criticism well ... haven't you heard, he's an offensive genius, QB whisperer, no one develops players better than MuLLLen.
Kidding aside, I am not sure Leach is any more of a genius than MuLLLen. You said his system works everywhere ... he's never won a conference (or a division?), and his record was 55-47 with a 2-4 bowl record at Washington St. I am not sure that's the definition of "works everywhere."
He can get all the players he wants, and he will still be ranked 8-12 in the SEC recruiting rankings. He's great for the game, but he's an oddball. There's a reason no top team has taken a shot at him. He's always one interview away from embarrassing the school. That from someone who really likes him in football.
As many have said here, he'll win some he shouldn't from time to time, and lose some he shouldn't from time to time.