I view most coaches who last a while as good coaches, but not singularly elite, that takes a while to become clear of course. Somebody spotted Urban Meyer and gave him a shot, he had success everywhere. Saban of course reloads each year and has an incredible run. Who else? I would lump the rest in the "pretty good" category, interchangeable in effect, you could swap them out with the coach at another school and see about the same results, aside from the "gimmick" coaches like Paul Johnson.