Dennis Erikson, etc.
While I agree there is some disconnect between college and pros in terms of coaching, Gruden would be a different deal altogether. Gruden is not "washed up" or a retread. This is a relatively young guy who has already won a super bowl and is doing pretty well this year with an average team. This is a guy that the Bucs "traded" draft picks for just for his coaching ability.
I am not saying he is Lombardi or anything. He is probably in the 2nd or 3rd tier of current NFL coaches though.