OK, let's see if anyone here can get really creative and come up with a result... any result that is clean beyond any shadow of doubt. Go back as far as you want. I contend that there are none.
I do not get too absorbed in all the current controversies over abuse, because I maintain that any Pro smart enough to read a race, is smart enough to prepare for it. And although preparation does, and has meant many things over the decades of cycling history, no one has ever won a major classic or grand tour with out some form of enhancement legal or otherwise.
The hairs continually being split on this site over "cheating" and "clean" are blurred by sentiment, hero worship, nationalism, and vilification, and all share the same subjective bias. Cheating is human nature. However we choose to justify it, or vilify it has no bearing on the fact that it is, and always will be a component of competition, and it is not limited to cycling.
My greatest hope is that the Blood Passport system accomplishes the potential affect of teaching every rider, and team physician how to effectively dope without causing undo scrutuny, which is to say maintain a level that is less than life threatening and on par with their breatheren in the peloton, and doping in sport can become less an issue. That is exactly the way it was before drug testing.
Why should we care if they dope as long as there is parity among the riders (something the Blood Passport might actually be good for). We certainly don't care in other sports like American Football or International Football. Their controls are a joke, and the fans don't care. An NFL players average LIFESPAN is 56 years! (52 for Lineman)
What's the point here?... Most ex Pro cyclist seem to age gracefully with apparently few reprecussions from their involvement in the sport. Unlike a Mohamad Ali, they go on to live a normal life. Why should we be so concerned with their biological safety, and post career quality of life when we are so much less concerned in other sports?
These are grown men who take life threatening risks in every race that they enter, and we the fans call it entertainment and the spirit of competition. If they choose to take other risks to remain competitive then that is also a matter for grown men to decide. They still have to train, they still have to compete, they still need talent and a unique physiology. The best of them are already freaks of nature anyway. Why should we be so concerned about what they do with their natural abilities? They couldn't have gotten there without them. It seems an absurd practice to be ruining the lives and livelihoods of a select and unfortunate few, for something that every pro participates in to a greater or lesser degree.