Original question may be old; the issue stays relevant.
I knew people involved in both in the 1980s.
I read Jose Silva's book, and it seemed harmless and like what doctors say about most natural remedies: can't hurt, might help.
All I remember is him describing the difference between people like his wife who are primarily visual (an NLP term he didn't use) all hyped up an
Forum: Large Group Awareness Training, "Human Potential"