I see the top 20 populated by Big 10 teams
http://www.teamrankings.com/college-football/stat/opponent-yards-per-play
I know there may be a flaw in racking up defensive stats against Big 10 offenses but I try to look at it objectively, though I often don't see that sort of thing. Boise State & TCU were near the top in yards per pass attempt defense during their mid-major heydays.
Yards per pass attempt D is usually a better predictor, Oregon moves up the rankings but so does Ohio State. Alabama predictably falls off their. Florida State is ranked #77 compared to their #51(right behind Oregon at #50) ranking in yards per play.
http://www.teamrankings.com/college-football/stat/opponent-yards-per-pass-attempt
Ohio State measures pretty well against the other 4 playoff participants. If anything, I'd argue they'd should be higher than a #4.
On edit - Arizona measures better defensively than Arizona State clearly in all categories so I was dead wrong, mid-season perception were behind my claims. I stopped paying close attention after the loss at Corvallis.
= new reply since forum marked as read