Lance was 175 pounds, or thereabout, before cancer.
130 pounds after cancer. He's worked hard to maintain that weight. Now build up the muscle and stamina of a healthy guy, and all the sudden you have the same body frame with a shitload more power than any other guy that weighs 130 pounds.
That'll give one hell of an advantage don't you think? Combine that with the worlds best trainers and nutritionists, and the worlds best bike (well, that's debateable) and you've got a rocket on wheels.
I give my support to Lance. And I believe he is not a cheater. A bit full of himself, yes, but wouldn't you be?