The advantage it might have had could go back to Armstrong's cancer therapy in 1996 which included EPO.
The pharmaceutical company providing it to him more than likely gave him inside information not available to others on its pharmacology. And from there he became skilled in its useage.
The company would have had a more than vested interest in his future success and given him what it could to aid in facilitating its useage and avoid its detection.
It would also have given him an excuse if he ever failed a drug test and an exemption for certain therapeutic useage.
It always seemed that the most likely avenue for Armstrong was his cancer treatment. Although that also shows the subjective nature of drug rules.
Armstrong was given specific permission to use a certain level of certain drugs that might otherwise be disallowed. How much? enough to still make it “fair” for everybody, but what is that?
What if we made a drug regime where everybody was allowed to test to a specific amount of a drug relative to their weight, so that people who were deficient in some factors could use drugs to “level the playing field”. That was the argument for Armstrong — that he needed these drugs, so it wasn’t fair to ban him.
They could have just as well said “We are glad you are getting cured of cancer, but while you are, you simply can’t be a part of our sport, because we have these rules”. But they didn’t — which shows they were NOT wedded to the idea of a drug ban, just that they could keep the sport from being a drug haven.
Armstrong would have been skilled at getting the “correct” amount of drugs, because he had to care about exactly what he tested. He would test positive for drugs, because he was taking drugs, and was limited in the amount, and had to keep that amount below the limits.
I don’t buy the company would have a vested interest — if they ever got caught, the bad would outweigh any good. And if Armstrong ever got caught, you could expect he’d blame the drug company for misleading him about testing.