If he stays, the read option stays. If Detmer refuses to let him run it, he will get smoked by Tanner. Taysoms mind just isn't as sharp as Tanner's. I'm not trying to rag on the kid, but he isn't an elite passer. Taysom is not an NFL QB, Tanner is.
With all that said, I freaking love Taysom and desperately want him back.