He isn't even the most tested cyclist, let alone the most tested athlete in history. Tie that up with payments to the UCI and conflicts of interest with the USADA and have a think about what might happen to any positive results. Armstrong has already collected a TUE after testing positive, EPO in his 1999 TdF B-samples (good enough for his EPO doping schedule to be determined), plenty of teammates and support staff reporting his using PEDs.