Waching Journey to Babel yesterday (needed a TOS fix), and there are so many examples of bad match-cutting it was amazing. For example, Sarek enters the rec room to take his pill. I the background, the Tellarite ambassador Gav sits casually sipping a drink with his left hand. Cut to a closeup of Gave, and he's sitting upright with the drink in his right hand. Cut back to the wide shot again and he's relaxed with it in his left again. That kind of thing.