Something I can reference, at least physical evidence would be nice considering the magnitude of the implications.
I'll try to find the source, but keep in mind, there are several things going on with this 'web'. 1) is that there wasn't a test for EPO or HGH for most of the time lance was riding 2) there are accounts (again, see hamilton's book and other reports) that riders knew when they were going to be tested and there were lapses in the rules and oversight which allowed riders to dodge tests all together. Most of the tests were based on the levels of certain markers in the blood, which could easily be dropped by drinking enough water or by waiting a few hours to be tested. The books is full of reports of testers who'd call the night before to tell riders they were coming the next day.
The benefit of a lot of the doping wasn't for longterm gains, it was for quick recovery and extra energy during the last week of stage races (like the tour). Blood bags didn't give a rider super strength or anything, but simply allowed them to push past their previous limits because of the extra red blood cells they had and such. The system was flawed and riders took advantage of it.
again, i'll try to find more stuff for you.