Brief history lesson for those here who are confused.
There was once a longhorn fan who rooted for ou. They hated to do it, they did it begrudgingly, but there was some logic suggesting it was the right thing to do.
As you might have guessed, bad things happened for that fan. Not just in the game, mind you, but also in life. The horrors that fell on that fan and their family would make Job blush.
For the rest of their days, as their once promising life wasted away, that longhorn fan looked back on the one decision to root for ou and saw it was the turning point where it all went downhill.
Don't be that longhorn fan. For the sake of your health, your family, and because it's fucking common sense, never, ever, ever root for ou.