Yes, you do mention a few riders, and it seems that the topic has now changed from all riders, which was my focus, to top riders, which is now your focus. Well, if some riders are doping and that's the reason why they are top riders, perhaps that would be true, that top riders are more likely to be dopers than other riders. But then you have to try to define what a top rider is.
I, frankly, have not considered Tyler to be anywhere near the level of cyclist that Lance Armstrong is. He seems to do very well on one day, and then the next day might fall flat on his face. Take the Vuelta TT that he won as a result. The very next day, he lost more than 10 minutes to the stage winner on the mountain stage. And Tyler is not supposed to be a bad climber. Something was amiss. His performance in the Tour de France was poor too, and then he goes on to win the TT at the Olympics. I wouldn't be too surprised if this turns out to be a true positive for him (ie, really did blood dope). But Tyler is one rider. There are many.
It seems like riders who dope often turn out to have done so when they are on the verge of retirement. They are faced with either retiring due to continued sub par performance, or they resort to drugs/doping. Tyler is one. Riis is another, Pantani, the list goes on. These riders may not have doped during their primes, but turn to it as a last resort.
And yes, I think EPO was getting used a lot more in the late 90's than it is now that the testing has improved. But there really are a lot of riders out there. I'd like to know exactly how many pro riders there are in the world now. That would be an interesting number. I think it's pretty high.
