Well, I do understand your point. Alabama first and foremost has to try to score, I wouldn't advocate the philosophy that Nick Saban employs sometimes (ending with a kick is a good result). But, they run a very high risk if they get into a shootout. Once Alabama's defense is worn out, that's that. There is no coming back from that, and that's how Alabama lost to Clemson in the championship game.
The last time Alabama lost a defensive battle was 2011 to LSU. Every other game was basically Alabama's defense not being able to stop the opponent and a lot of the time it involved the defense not being able to keep up with the pace. Granted, a healthy Tua could mean that Oklahoma can't stop Alabama, but what is Alabama doing to buttress the defense and give them a shot against Oklahoma? Quick 3 and outs, or even quick scores will put the defense right back out there and at the pace that Oklahoma plays, that could quickly become a problem.
I think Army is the best running team Oklahoma has played, but I'd never advocate just trying to run their offense. Army averages like 4.66 a rush though. Alabama averages 5.34. So, here's how I see it., Alabama has to protect Tua. Each time he drops back, that's a risk. It's a risk for an in completion, a risk for a turnover, and a risk that he gets hurt. Each time Alabama runs the ball, they're punching Oklahoma in the mouth potentially, Oklahoma gives up over 4 per run, Alabama should be able to control the game and protect Tua by running the ball. It doesn't mean they shouldn't throw it, but if they become over-reliant on the pass, well that's been the only weakness Alabama has shown all year. The only reason Alabama even got in trouble against Georgia was they had a dropped pass that resulted in a three out and that gave Georgia the ball right back in prime field position and deprived Alabama's defense a chance to rest. They can't afford that against Oklahoma, if Alabama's defense can't rest, Oklahoma is going to start scoring.