I am reading through the numerous "Dagger" story outlines, and the first two versions are almost entirely unlike what follows and what we got. Anyway…
I don't have all the script drafts handy, but I can tell you how the trajectory went with the hypnosis…
- 1966-3-(day not marked) story outline: Van Gelder is beamed down with Kirk and Yeoman Xenia Todhunter
- 1966-3-30 story outline: Van Gelder is beamed down with Kirk and Yeoman Colt
1966-4-14 memo: NBC & Staff Comments, "Dagger of the Mind", p.4.: "It gives us a chance to explore Mr. Spock's logical turn of mind, his enormous shrewdness, perhaps even introduce some other traits such as an ability at some alien form of hypnosis which may be not only interesting but useful to us in future stories."
- 1966-4-25 story outline: Van Gelder is beamed down with Kirk and Yeoman Rand
Henceforth, Van Gelder remains on the Enterprise when Kirk beams down
- 1966-5-2 story outline: Van Gelder agrees to hypnosis, but who performs it is not specified
- 1966-5-9 story outline: Van Gelder agrees to hypnosis, performed by Spock
1966-5-20 NBC's program standards chimed in regarding the May 9 story outline and Spock being a hypnotist:
In accordance with our precautions to avoid hypnotizing a viewer, the act of hypnotizing must be either out of context
or done off-camera. Further, since you are portraying hypnotism as a legitimate medical tool Van Gelder should be hypnotized by Doctor McCoy rather than Mister Spock unless Mister Spock can be established as being qualified in the use of this technique.
If you would like a clinical reference, please feel free to contact the local representative of the Society of Clinical
& Experimental Hypnosis: Newton W. Bernauer, Ph. D,
1966-6-27 "revised screenplay": Spock uses some "goggles" to get through to Van Gelder. There's a handwritten "hypnogenic" .
1966-06-28 memo from Bob Justman on this "revised screenplay": He writes, "Luckily, on page 35, Spock goes into his famed hypnotic routine. He sure is a handy sort of fellow to have on board a space ship."
There are undated later handwritten notes for the 1966-6-27 "revised screenplay" that mention Spock "painfully charges up his resource of psychic energy for the ordeal he is about to under go".
1966-07-22 NBC program standards reiterates what they wrote on May 20 regarding hypnosis, so the mind joining must not have been in the 1966-7-6 yellow cover script.
1966-08-09 NBC program standards memo on the 1966-08-05 red cover script does not mention hypnosis, but mentions Helen Noel, which confirms Rand was out of the script by this point.