Ulrich, Basso, et al have never tested positive either. But it looks pretty clear cut that they're dopers. Ulrich could easily take a DNA test to prove his innocence, but he won't do it. Why do you think that is? He's never tested positive, mind you.
Heras tested positive ONE time on the second to last stage of the Vuelta when he already had it in the bag...do you think that was the only time he did it??? With everything to lose and nothing to gain??? That was just the time he got caught.
You're demonstrating your lack of knowledge every time you open your mouth.
So tell me again, what is the explanation for Landis??? Oh yeah, the world hates Americans. Or maybe it was his twin who died in his mother's womb (the Tyler Hamilton defense). Or it was the Jack and Cokes? No, that's not it...some Frog slipped him a Mickey the night before and he just happened to blow everyone away unlike anything that's EVER been seen before in the Tour!!! Hey, Yobid...if the glove doesn't fit, you must acquit.