Lance's publicist has of course denied the that he is a credible source, but lends no claims other than "He's was the most tested athlete" and that Mr. Hamilton is only doing this to gain publicity for his book. Now this is what we call in the Philosophy world as a Red Herring and a personal attack. Neither one of these refutes the claim and is only a way to distract the listener from the fact that there's really no claim being made.
Now, I will lay out I do believe at one point in his career lance took a banned substance. I don't know when it was or how long or in what context. Though, I do believe that an important step forward is to accept that the sport has a problem and then learn from it. If for no other reason than to give hope to individuals who are trying to make it into the pro ranks now. The first step to cleaning the peloton is airing out it's "dirty laundry" so that we can start to solve the problem in it's entirety. Make it transparent, we don't have to know everyones Biological Passport and their test results, but knowing what the doping agencies are doing to combat this horrible scourge of the peloton would be a good start. The problem has to be attacked head on, and I'm sure a lot of Pro's and team members will be hurt and lose their job, but it will be in no way even close to how much they've already hurt the sport.