I agree with everything but this part, he seemed to run a "spread" style offense just fine when Pryor was here. He played for the victory rather than the style points. I think that is what drove most people crazy. Had he won against Texas in 05 or USC in 08 and 09, I don't think you'd hear people talking about him playing conservative as much as you do. If you look at the years where he had the playmakers, he put up points.
With that said, I honestly see Tress coaching ever again.