I'll vote for ad9898 for a few reasons.
He has a join date of three years ago and says he reads the forum but seldom posts, yet he tried to dismiss Armstrong's EPO positives off as an Internet rumor. That comes off as spin control, something Armstrong has often used.
He does not want to discuss the evidence that Armstrong doped, but prefers to make the argument that as long as he does not get convicted in a court of law then Armstrong is in the clear.
He is free to admit that he had testicular cancer but has made the dubious claim that he was faster on bike after treatment than he was before. Armstrong has also used people's lack of knowledge about his treatment to build himself up in the press.
He mentions that posters on many forums are convinced that Armstrong doped, indicating that he might be keeping tabs on what is being said, and he says that he will stop posting here and post again in a few months, indicating a sort of drive by trolling that might be expected from someone who was interested in how he was perceived.
Most of the other pro-Armstrong posters have enough posts with enough information to make me think they are not Armstrong. The exception is ih8lance.