Oubliette - There are a large number of manipulative techniques which do not require
disconfirming evidence and a corresponding "doubling down" on the part
of the person being manipulated.
I agree with this. There certainly are other important manipulation factors involved.
What I am mostly referring to is the "glue" that makes one's belief rather impervious to contrary evidence. In my own experience, (and from what I have seen from many on this board as well), I saw things that were not "right" years before I left. Things that I know now, would have been obvious to me had I not already had the mental investment in the belief system. Cognitions are very powerful, especially for thinking type people. Thinking types have a low tolerance for dissonance in this area, (Feeling types may rationalize more easily). So one ends up faced with a choice, either make the painful change of accepting that one's belief system is wrong, or simply push the disconfirming evidence away. Since this happens primarily subconsciously, that latter is almost a given.
This is a subtle, yet considerable factor as to why otherwise intelligent people cannot see something obvious, such as TTATT. Fear is a big factor, however the fear we are discussing in this context is mostly existential in nature. One is mostly fearful of losing their understanding of the way the world works, even though they almost certainly do not recognize it as such.
d4g