Sorry, but the definition of a "great coach" is someone who transcends their situation and takes their team to something more than a 58% winning record (and that's minus his first two years). If you look at Rutgers operating budget during Schiano's years, Rutgers was very much in the same tier of operating budget as schools like VT, Louisville, WVU, etc. Yet still only 1 top 25 season in 11 years? That's an OK or even good coach...not a great coach. He's a tremendous DC, but as HC not nearly the same level. (BTW, Schiano was the highest paid HC in the Big East when he left.)
http://sports.usatoday.com/ncaa/finances/
Let's compare Schiano to CPJ's situation at Navy. CPJ took over what many considered a hopeless situation coaching a military academy. In his six seasons at Navy, they qualified for 5 bowl games, and ended the season of 2004 ranked 10-2 and ranked #24. So in almost half the time, CPJ was able to qualify for just as many bowls (CPJ 5, Schiano 6) and was able to match Schiano in the number of seasons ranked in the top 25.
James Franklin, in 3 years at Vanderbilt playing in arguably the toughest conference at the time (SEC), was able to qualify for half as many bowls (3) and was able to end the season ranked twice as many times as Schiano...in less than a third of the time.
The jobs of Franklin and CPJ at Vandy and Navy in similar circumstances are examples of very good to great coaching jobs. Schiano at Rutgers? I'll let others decide on that, but from my perspective, he did OK to good.
Answer this: If Schiano was as good of a coach as you want to believe, how come the many teams across college football that have needed a "great head coach" since he was fired from Tampa in 2013 never stepped in to try and hire him until Tennessee this weekend? Saban was hired before he finished out the year in Miami, Chip Kelly had every major program with an opening lining up to hire him the last 2 years. "Great head coaches" aren't left coaching high school and being a position coach until OSU hired him to be a DC.