Not to Saban's level, no. And he ran from USC sanctions, more than anything else. But he's the closest example.
And it is a valid point, but there are only so many NFL jobs available, and tons of college gigs, so that exact scenario would be tough to pin down even if there weren't other issues like control, owner input, drafting, free agency, etc etc. If anyone were going to be the first, I'd wager it will be Harbraugh. He's young enough to make that move again, if he wants.
No way in hell he leaves Michigan after only one season. I'm actually beginning to think he never leaves.
Longevity? In this day and age? Personally, I'd like to see Harbaugh have a Schembechler type tenure.
Pete Carroll Jimmy Johnson "Barry Switzer" (I put this in quotes because he was just driving a well oiled machine that was already made for him) Just off the top of my head. edit: and that is what I get for not reading the entire thred before posting