During my time in competition, I never tested positive (or non-negative, as they like to say today). Neither did a lot of people who also rode in that period. We got our fair shares of success and suffering. In the end, if everyone is completely clean, or just a little bit naughty, or worse, they all still have to turn the pedals, and a view which I have heard is that all that's needed is a level playing field, where the best still succeed and get the results which keeps the sponsor happy, and ensures a living for another season.
There is the conundrum for the rider, do you let yourself get hammered by better "prepared" riders, or do what you have to do to level the field, or carry on getting battered and hope the others get caught? Because generally they didn't, until recently, but I'm coming to think that the sport is cleaner than it's been for a long time.
Now, Mr Armstrong won his races with dedication to a single cause (when did you ever see him really "perform" in anything other than the TdF, unless for training?), and always arrived at the start of the Tour fully prepared, with a dedicated team, and at a peak of form. Then beat others who may have been "prepared" very well by their medical support. Simple question, is the man a superb athlete (yes), was he at a peak of form and could hold it for three weeks (yes), how did he manage to beat riders who have since admitted their use of illegal methods, whilst remaining totally unsullied (don't know but think about it).