He painted them knowing which drug he was under the influence of, thus the result is just as much (if not more so) a reflection of expected (or known) effects of the drugs as the actual effect the drugs themselves had on him. If there was a way to blindly administer the drugs, I might be a little more swayed.
When I was a kid my mom took mushrooms and did a self-portrait for a class she was taking. All I remember about it was that it was entirely in red colored pencil and very strident looking.
#2 - what makes him a fraud? He never claimed to be ignorant of what drugs he was taking. I think it was still an interesting experiment. I also watched one of his spoken-word performances (not something I'm generally interested in) and was impressed.
Fraud status confirmed.