Classic SEC propoganda, though not on your part. I mean who could blame you, it gets hammered into your head on virtually every college football show looking to sprout off nonsense.
For some reason SEC supporters feel they have to downplay the quality of all the other conferences at the sake of talking up their own. A few years ago the SEC really was a deep conference but it now resembles the PAC-10 before this year, with one or two dominant teams and everyone else. Outside of Florida and Alabama you basically have a bunch of teams that refuse to play quality out of conference teams, not to mention the fact that Florida and Bama aren't really looking for quality out of conference opponents themselves. Say what you want about Ohio State but at least they put USC and Texas on their schedules. By the way Bama lucked out with McCoy going out of the game on the fifth play of the game.
So how does this relate to the Big XII? Well to be honest they have something that the SEC usually doesn't posses. Good QB play. Seriously most SEC offenses are run the ball 40 times a game, throw 20 passes and hope you complete 11 (believe me I'm constantly lulled to sleep by SEC games on Saturdays during the Fall). Which is fine, but it tends to make the defenses look better then they really are. In fact the only true test SEC defenses get on a yearly basis is Florida and they usually fail that test miserably. That is why the only defense I'm even prepared to acknowledge in the SEC is Alabama's.
I'm tired of Big XII QB's getting downplayed because "Oh no dey didn't dun pleh against them SEC defences no sir ree." This is top class FBS talent they're going against. It just so happens that the Big 12 has competent offensive coordinators and better QB's, so it ends up in the defenses getting downplayed.
So in short the perceived dominance of SEC defenses are a joke while many Big XII defenses are underrated. Most of the offenses SEC teams go against use gameplans that would insult an NFL preseason gameplan. All the while Big 12 defenses go against some of the most well coached offenses in college football, and get punished for it.
Anyway sorry for the rant but this had to be said.
In the meantime here's some Anti-SEC propoganda. I know it's from bleacher report but this one is backed up with facts.
Let's Face It, the SEC Is Overrated This Season | Bleacher Report