This is about as cynical and paranoid as I can get. So I'm only putting forward for public entertainment.
IF the USADA's accusations are correct, then it can be said that Lance must have acted as Barry Bonds has been said to have done - "Do what I want, win everything, deny everything, let public opinion sort it all out."
Lance's back story has always been that he was an arrogant hotshot when he was young, and cancer humbled him and the trial he endured helped him to become a great champion. IF the USADA's accusations are correct, it can be gathered that he never actually changed at all.
As burnsy's question alone points out, Lance never has to publicly voice his cover... "But look, I'm an American hero who saved lives." Others will do that for him.
One thing doctors have to do is forecast the future of medicine. It has been proven again and again, PED docs are especially good at this - it's essentially all they're trying to do, whether it's in the name of sport or not. (I actually think Victor Conte sounds like a really smart guy.) Is it not possible that seventeen years ago, Dr. Michele Ferrari or someone like him said "You know, over the next two decades cancer rates are only going to skyrocket..."
IF the USADA's accusations are correct, and Lance has been misleading the public about everything, is it not possible that Lance NEVER HAD cancer?