I thought that scene with Garth and Spock really worked. Spock underplayed it perfectly. Was it something like,
Spock: Captain Garth, I -
Garth: LORD Garth!
Spock: As you wish. In any event...
I thought Spock's refusal to acknowledge the outburst was perfectly in character.
Loved the episode, especially the first time I saw it in the 70s and I didn't know all the twists.
And, yeah, Yvonne Craig is beautiful.