long term use of testosterone causes your own body's (err, I mean "your own organism's"... lol) production to decrease. I don't know the medical details enough to know whether this would have interfered during the race, but it's conceivable that he had to keep taking it once he started.
I sympathize with Floyd's side of the argument but I haven't seen him make any effective rebuttal to the multiple B samples from earlier in the Tour that they went back and tested. I've read Floyd's book, which means that I've only heard his side of the argument; I expect that the 84-page decision document will be posted to Trust But Verify
sometime soon so that we can all hear the prosecution's case for once, in addition to Floyd's litany of appeals to emotion.