It's easy to point the finger and say it's the acid's fault, but what about all the schizophrenics who never took a drug in their life?
Of course, there are people who also think that people who have a predilection to psychosis are also more likely to try drugs as a form of self-medication.
I'm not pro or con drugs in general, with the exception of thinking that marijuana laws are somewhat baffling; but this seems like one of those cases where otherwise highly logical people get sucked in by convenient explanations, regardless of their basis (or lack thereof) in fact.
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Editing to provide my own counterpoint: Since I honestly don't have any kind of deep knowledge on the matter, I spent some time with Google and found this:
http://en.wikipedia.org/wiki/Hallucinogen_persisting_percept...
as well as:
http://bjp.rcpsych.org/cgi/content/abstract/118/543/229
Make your own judgments, I suppose.
However, drug use in our society doesn't occur under such safe circumstances, and I know people who have been burned by drug use. One is a schizophrenic who used obscene amounts of ecstasy, shrooms, salvia and DMT throughout his 20s and early 30s. When he was 24, he was popular, a great basketball player, and able to interact normally with other people. At 35, he's incapable of holding a job and has been in trouble with the law countless times. His psychological collapse might have happened anyway had he not been using psychedelic drugs, but I suspect it wouldn't have happened in the same way, and it might have been more manageable.
I don't know anyone, though, who has burned out on a small amount of psychedelic drug use. I believe it can probably happen, but I've never seen it. Also, there are a lot of people out there who've used these drugs and had few or no ill effects, and their cases simply aren't reported.