If it were all simple incompetence, then the laws of probability say we would benefit from the "mistakes" as often as be hurt by them.
But when incompetence appears to run overwhelmingly in one direction only, the more accurate word for it is "bias."
Though the SEC refs embarrassed their league in primetime, they did call an honest game at the end...the non-call on pass interference in the end zone, the near safety, the defensive pass interference against Dotson...all critical plays called correctly.
For some reason, I'm more bothered by the performance of our own conference's refs. The SEC guys may be biased in favor of their league. But the Big Suck guys are biased against Penn State.