I remember the case of Pedro Delgado in 1988. And this goes to show how much has changed around doping in the tour, with Rasmussen removed, shortly before winning the tour.
In 1988, Delgado was about to win the tour, when he tested positive on a drug that was not yet banned, but sure soon was going to be. It was not doping in itself, but it was a masking drug, a drug to throw off tests on real doping. This news came out a few days before he was going to arrive in Paris in yellow. Delgado was not removed, not banned, not punished - he won the tour and has not even be removed from the list afterwards.
The number 2 of that tour, Steven Rooks, I remember, wouldn't hear of it either. He said Delgado was the true winner. Period. But surely he was suspect. More that that, in a way it could be proven he was drugged. He was drugged with the masking drug. Who would use that drug, other than for masking. But no scandal ever was made out of that.
On Rasmussen nothing is proved, but being suspicious these days is enough to be taken out and not even compete. Taken out at the very end if it must. That is what has changed and I still wonder whether that is for the better. We know who won in 1988. We don't know who won in 2006, and we may not be sure about 2007.