Watson's mentioned that he does occasional consulting work for biotech companies and that he's legally prevented from trading their stock. I'm pretty sure in some of his older comments that I still have (they're no longer on yahoo) he talks about trading ambs and other stocks. If he is what he claims to be and trades his client's stock that seems like a very good reason to wish to remain anonymous. I will look for those quotes later.

What he does might not even be considered insider trading -- maybe it would create a problem for him as a consultant -- lack of impartiality, unethical behavior, breach of consulting contract or something like that, I don't know, I'm just a commercial artist. I don't know who he is but I agree with Warp and others -- I find his posts informative, regardless of who he is he seems to know much more about biotech than I do.