One common measure of a coach is former assistants that translated into Head Coaches. Stoops(s), (both of them?) and Mangino come to mind. What others am I missing?
Snyder is part of the Hayden Fry Iowa coaching tree, as is Barry Alvarez at Wisconsin... both now step down. What made Bill Snyder's transformation of a football program significant is that it was accomplished at Kansas State. If you've ever been "to or through" Manhattan, Kansas, you know exactly what I'm talking about. It's closer to nowhere than Starkville. ...and that will be his legacy... regardless of a school's lack of football history or tradition, it is a "Bill Snyder" away from 15 minutes of fame.... job well done, Bill.
His QB Roberson was accused of rape the night before the Fiesta Bowl and he allowed him to play the game.
Or, he beat OU, thereby dethroning them as "the greatest team ever," which allowed USC to claim a piece of OUR NC.