I would bet doping of one kind or another is routine in and around CFB. I doubt it's sanctioned by many schools, but I bet they are largely ok with presenting a front to the public that looks like they are addressing the issue, without investing in the resources to really crack down.
MLB is a pretty good barometer. It has a strict guideline for drug test failures, and yet every year people--including stars--get caught. They wouldn't get caught if they didn't think they could get away with it, and if they think they can get away with it, that's because people do. So they are catching a small percentage of the cheats.
Professional bike racing and the Olympics are also pretty demonstrative. Those testing regimes there are extremely strict and quite active, and yet people--including the stars--routinely get caught. Same as with MLB: if they thought they would get caught, they wouldn't do it.
The incentive to cheat is strong and the technology is there to keep ahead of the testing. The physical feats these guys are pulling off are remarkable. Sure, some of them are the result of lucky genes, some are the result of legitimate research in strength and conditioning training, and some--probably a significant part--are the result of "science" and keeping ahead of the testing regime.
Truly just an opinion, but a strongly held one. :-)