There are a couple things that have been different about Lance and steroids versus MLB and NFL players and steroids. First, Lance has been tested more times than every player who has ever played Major League Baseball combined. Some of them has been tested only once or twice in their lives, and they are NEVER tested between October and February, when they are at home pumping iron...duh...
Second, by filing lawsuits against every person who has accused him of using steroids, Lance is SEEKING the opportunity to deny taking steroids under oath, subject to going to prison for perjury. In contrast, when Barry Bonds was under oath at a Grand Jury, he admitted taking steroids, but said his trainer lied to him about what he was giving Barry...Bonds claims he took steroids by accident. Last week, Mark McGuire had the opportunity, under oath, to deny ever taking steroids...he refused to answer the question, but attacked all of the folks who have been fighting against steroids.
So, why believe Lance? The most tested "star" athlete in history. The only "star" who LOOKS for opportunities to force his accusers to testify under oath, and who is eager to testify under oath himself.
My "guesstimate" of the odds that Lance has used steroids in the past seven years? Zero.