Originally Posted by Brian Ratliff

Actually, more likely that Lance was doping (maybe, probably, on and off) his entire career, comes back and is now perfectly clean. It's really a no-loss situation for him. He comes back after a 3 year break and if he can't win the tour, he has the perfect excuse. If he comes close, then he can say that he didn't need the dope. Meanwhile, he gets tested 40 billion times, always coming up clean because he is clean (this time around), and slowly scrubs his name of this doping stuff.

Just speculation. But it makes more sense than to go back to the lion's den when the lion has had three more years to make up new tricks for catching him.