If psychology lacks credibility then NLP lacks credibility two fold.
Certainly. But there is a wide gap between psychology and NLP in the weight of the claims. Most of the wordings I remember from Bandler's books were light-hearted and open-ended. From what I've gleaned of psychology, it is often used as an authority to make definitive claims about the nature and quality of people. "He is that
. She has this
, therefore she does that
Bandler would take the stance "how can we know?" (because ultimately it isn't verifiable) and leave it open as to what could be done. Labeling states and conditions is something Bandler would oppose, as it in itself affects self image and behaviour.
I'm not sure what you mean in the above paragraph but NLP makes testable claims and such claims are therefore subject to the scientific method. If you choose to contend that NLP does not make testable claims then why should you or I take it seriously?
I would guess that, depending on how the claims are phrased, they are not testable to an extent that would make a difference. Basically, the point of NLP is to sway cognitive bias. It is not meant to be trusted, rather to be used as a form of exercise as long as it works.
From the way it looks, the point of psychology is to provide an opaque volume of material from which psychologists and pharmacists may lend authority when they judge people and ordinate medications. Ofcourse, it may have different meanings to different people.
As to your first statement in this paragraph, science is an authority, so I do not agree when you argue that there are no authorities when it comes to human knowledge.
We should recognize that science is a method, and the authority comes from evidence gained from science. It can never be an authority over things which are untestable.
There are forms of human knowledge that may be untestable, for example artistic talent, and so on. Is it possible to test if an artwork is good before we show it to an audience? If the test has to include the audience, is it repeatable?
I have already pointed out that NLP can seem to work for some people because of the power of suggestion, the power of suggestion is real.
For NLP, there is no difference between "seeming to work" and "working as intended".