@Maurice
Regarding Spock's mind meld with van Gelder,
I thought the point was that the Vulcan mind meld is not hypnotism.
It was a long time ago so my memory may be wrong but I thought I read that at ffirst NBC thought the mind meld was hypnotism and they wanted an official medical doctor, McCoy to do it. So it had to be explained to them what a mind meld was and why Spock can do it and not McCoy.
So in that NBC memo you quoted, I'm not sure why they're providing guidelines for how to depict hypnotism when it's not.
As I said, my memory may be wrong and if it is, I'd like to be set straight. I'm talking about reading stuff like TMoST and The World of Star Trek way back in the 70s.
Robert