You touched on it, but many of the articles I've seen really hammer on how bad OU's defense was last year - definitely warranted early on - without taking into account the second half of the season. They essentially went from the worst D in college football to a much stronger unit that made significant improvements under a first year d coordinator.
In their final 7 games they held teams to an average of 16.4 ppg, which would've been 8th in FBS. They're certainly not THAT good, but they're not a dumpster fire as most have made it seem.
That might be the key to OU's entire season. OU can score at will, can they stop teams (consistently enough) to win?
All-in-all, good stuff. I see you were too scared to get into the prediction business. ;)