Corrected entry: Garth, shape-shifted as Spock, applies the Vulcan nerve pinch to Marta. Since Garth can only imitate the physical appearance of someone and not that person's life experience, Garth would have no knowledge of the Vulcan nerve pinch. The same could be said of when Garth shape shifts into Kirk - if Garth had Kirk's knowledge, he would have known the counter sign that Scotty used to challenge him for the beam up.
Correction: Garth, prior to being able to shape-shift and going insane, was a well respected Starfleet Captain and skilled tactician. In fact, he was required reading at the academy. Captain Garth would no doubt have extensive knowledge of Vulcans and the Vulcan nerve pinch, including learning how to do it.
Correction: Kirk indicated to Marple and Chekhov that someone or something was behind the rock that Spock nodded towards to show Kirk where their "friend" was. Kirk told Marple to "cut around the rock to your right", meaning the the man go around the indicated rock (behind Spock) so that his movements would be to his right, thereby keeping the rock to his right.
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