Defending the spread
First I admit that I haven't watched every down but when we defend the spread how often are we in like a 3-3-5 or a 4-2-5.
Going to the nickel wouldn't be that bad. It seems that corner is fairly deep for us so why not pick 4 of them(Johnson, Benton, Bell and Singleton or McDowell), and put them with James Smith.
I'm sure we'd still get burned somehow but at least the coverage is better and the LBs(since we only have to use 2 at a time) would be fresher.
Re: Defending the spread
I am a fan of a nickel type defense against spread teams. Against Okie St, a 4-3 is probably a must based on their balanced attack.