I think what you saw was a combination of things. First, you had a Texas team playing with no pressure ... everybody expected Oklahoma not just to win, but to win solidly. Second, Oklahoma had flaws that Texas was pretty qualified to attack. With Jordan Phillips and Corey Nelson out, the Sooners were hurting up the middle and lacked the strength to take on the Texas power running game. On the other side of the ball, Blake Bell's limitations as a passer allowed Texas to really concentrate on stopping the Sooners from running. And lastly, I think Texas had an outstanding gameplan and attacked those weaknesses on both sides of the ball.
It's hard to say that when the team, and David Ash, expects Ash to be back eventually. Now, when he comes back, does Texas interrupt its current chemistry and flow to plug Ash back in, especially if Case McCoy is still undefeated in the Big 12? I think you do. This offense was built around Ash's skill-set, his ability to stress a defense horizontally and vertically with his arm strength and his ability to take off in the quarterback run game. Granted, against Oklahoma, the offense was somewhat retooled. Texas reined in the spread formations and didn't ask McCoy to make long throws to the field side. Instead, the Longhorns bunched things in more and asked McCoy to be more of a caretaker, a role that he filled admirably. McCoy can be pretty accurate, and he's cut way down on his mistakes this year. He's staying more in the pocket and not trying to do too much.
3. The defense has vastly improved; was it more of a bad scheme by Diaz that the players never bought into, or is it just the new intensity from Greg Robinson that's transformed the unit.
I think you're probably seeing a little of both. I don't know necessarily that it was Diaz's scheme that was bad ... as the old coaching saying goes, everything you draw on a chalkboard is sound. I think, for whatever reason, he struggled to teach the players how to perform their roles within that scheme. When Robinson took over, first he simplified things, and you started to get reports that he was working on things like leverage and helmet placement when taking on blocks. As weird as it sounds, those are some of the things that were really lacking. Texas's players not only weren't getting to the right spot at the right time, but they weren't doing the correct fundamental things upon arriving. So much of what Robinson has done would fall under the "teaching" headline, and when coupled with his passion and excitement level, it gave the team a major boost.
4. Last season TCU came to Austin and was able to beat the Longhorns on Thanksgiving with a good run game. Does that loss weigh heavily in the players' minds or are they just looking at this as another game?
Honestly, I don't see how it couldn't. While the Texas players aren't calling it a revenge game, they have certainly acknowledged that last year's game was a missed opportunity. Not only did they make mistakes by turning the ball over, their running game was shut down and they allowed TCU to run for over 200 yards. And on Thanksgiving, no less. So I don't think the team sees this as just another game on the schedule. And whatever they say publicly, I think this one matters a bit more.
5. What are your keys to a Texas victory?
I think everyone knows this is going to be a physical game. Texas's offensive line has jelled pretty well, in fact, the left side with Donald Hawkins and Trey Hopkins has been pretty dominant in recent weeks. The key for Texas will be to ride those guys, along with Johnathan Gray and a now-healthy Malcolm Brown, to put McCoy in better situations. The one thing Texas doesn't want is to toss McCoy in too many long second and third down situations, because that's when the TCU defense, with its double-teams and pattern-matching will slam the door shut. Defensively, not only is stopping the run key, but also stopping the unscheduled run, meaning keeping Trevone Boykin from hurting the Longhorns in scramble situations. He did that several times on TCU's scoring drives last year, and that wound up being one of the main differences in the game.