It's an interesting question, but the way we saw it was very much the opposite, at least through the Stoops era. Still related to refs, but we always believed that OU's offense was predicated around BigXII refs being very tight on PI calls, giving the receivers more free run in the secondary, forcing defenders to be too passive in coverage. Then, when BCS games or Playoff games hit, the much looser ACC or Big 10 officials would allow just about anything short of a full tackle downfield. OU's passing game wasn't able to adjust, and the defenses couldn't magically become more physical for one game to take advantage of the shift. Watch the Florida/OU 2008 game for a prime example of this, in my opinion. OU averaged 7.5 penalties a game that year, and got 4 called on them in the title game. Florida was taking heads off in the secondary with little to no repercussions.
The second point tex makes definitely reflects Grinch trying to adapt our play to the national style and prepare for competition outside the BigXII. This is a wise move, and hopefully helps to address everyone's concern that OU for years has been content winning the BigXII and being pantsed in the postseason.
I also want to be clear, this is in no way blaming refs for OU's failures. If this is something a fan notices, then a coach has to be responsible enough to realize the same things and make systemic change to keep it from happening in the future. They should have seen in 2003 things were trending the wrong way, but I believe Bob truly thought he had to play to win the BigXII first and let the dice roll for everything after that.