PSI looks like a clever packaging of the human potential teachings of the 70's with a bit of California new-age flair. The word "vibrations" was actually used on the PSI website. <smirk> The name PSI is almost a self-parody, really, being the engineering designation for pressure, as in inflated, after all. <smiles>
I have little stomach for such hype, but it is a free country. My intuitive feel is that this is not a sociological cult, nor really a doctrinal cult of any other religion; it is just a rehashing of self-delusion teaching. I do think it is dangerous and wrong, mind you, but not for cult reasons. Rather it is just bad advice and teaching.
Take a man who is unethical and untrustworthy and who destroys trust in those he works with, ruining a great business he is involved with. Well, these failures might lead to reflection, repentance, and change, but not if he falls in with PSI types. With PSI, the business failure was not due to character flaws and poor ethics, but his "attitude". If you follow me here, any honest reflection on character deficiencies which ought to be the normative feedback from failure in life are short-circuited as "negative"... and such normal feedback is actually BLAMED for the failure instead. Thus, real growth and improvement in actual ability is not possible. Instead, false confidence is given through "goal setting" and "visualization" and so forth, and our man is going to hurt people--and himself--more next time if he continues to coat-over his real problems. If he ripped people off the first time, and they abandoned him, shall we give his "confidence" a hypo and send him back for more of the same... or shall we "negatively" look to the real causes of failure?
A more sweeping critique is that PSI is the intellectual equivalent of injecting yourself with HIV. AIDS is a deficiency of the immune system, which normally acts to attack that which does not belong in the body. By analogy, "negative" feedback acts to attack that which does not belong in the character. By thinking only "positively", the character immune system is sabotaged, and the results will be a mentally sick person; perhaps incurably.
For example, some people are for various reasons mentally divorced from reality and deluded. We call them "insane" or "crazy". Perhaps it was a chemical imbalance, or some horrific event in life that pushed them over the edge of reality. You must now address them as "King Henry the Fifth" and so forth, and they are generally locked up or strapped down. If you tell "King Henry" he is really John Scwartz and you are his older brother, he will say "Off with his head". For "King Henry" does not like being John Schwartz for whatever reason, so he projects a delusion more to his emotional liking, and rejects all reality to the contrary. John is deluded, and the situation is pathetic.
But their is something even more pathetic than someone driven to delusion by the pain of life, or genetic or chemical imbalance. It is when normal, semi-sane people will sell-out reality for an imaginary "success". This is delusion in degrees, to be sure, but the pathetic thing is that it is self-inflicted. Such delusion does not make one better at life, any more than "King Henry" really has any power to really decapitate anyone outside of his own imagination. And "King Henry" can't help it, perhaps, but the PSI customer is paying to enter deliberately and substantially into the same state. Delusion for sale.
If success can be had by these hollow, self-absorbed hypsters, it will be in spite of this training, not because of it. Somebody might inject themselves with HIV and not get AIDS, but this should not endorse an otherwise dangerous practice. Likewise, should we be injecting our minds with delusions of grandeur? Like HIV, the real and present danger is that such reckless mental activity might lead to a breakdown in the mind's immune system, which in healthy people serves to kill-off bad habits and learn from mistakes. PSI is the virus to put this normal mental function into atrophy or actually shut it down completely. Another "King Henry" is made, only this one paid for the privilege.
Related articles: Wrestling with ghosts: Do people tend to have "negative self-images" and need to be encouraged to be "positive" in actual fact?
For a biblical take on reality and self-assessment, see the Bible Study on The Light.