In nearly all of their big runs, the OSU OL were able to get to the 2nd level and pick off multiple LBs to give a clear lane to the RB. I think Coburn demands a full double team. He's going to make it difficult for the guard to combo then hit an ILB without giving up penetration that can blow up an inside run - which is most of their ground arsenal. Even if they are successful single blocking both DEs, that only leaves one O-Lineman than can attack the LBs.
Orlando has played the Buck LB off the LOS against the spread quite a bit and a 3-3 stack creates tough angles for blockers looking to seal off pursuit at the 2nd level. It's a lot harder to block the BLB there than if he gets tangled up with an OT or TE at the LOS. Also, OSU isn't a team that runs a lot of toss sweep or stretch where you need a C-gap defender from the snap. They mostly rely on inside zone concepts (esp. tite and split zone) and power/counter.
I would have said dime but with the injuries to Overshown and BJ Foster I think Texas has to play Nickel with Chris Brown near the LOS where he can set the edge against the run. There isn't a 2nd DB available with that ability to blow up blocks and hammer the RB. Setting up in a cover 2 shell then rotating one safety down to the 2nd level is going to create that free hitter in the box against the run. Doing it late in the clock puts it on the QB to ID the coverage quickly, then make the right read and throw. I'd love for that extra guy to be BJ but that's not in the cards.