Ever heard of George Welsh? Left Penn State to coach Navy, then went on to UVa.
I know when you have a successful football progrem, coaches are raided by other schools.
It seems odd for coaches to stay at one place for so long and not have any ambition to move on to a head coaching job.
Bill Parcells, in his autobio. stated that is what asst. coaches are looking forward to, their own hc job, not remaing asst. for the rest of their careers.