Yep, Spock totally peaces out possibly gets laid before Kirk crushes the happiness out of him.

I think the deal is, if Kirk's not happy, then nobody else gets to be happy. Did you ever see the space hippies episode? The one where Spock jammed with the hippies on his Vulcan harp? Good times. I think Kirk just doesn't like it when happy people are around to point out what a square he really is.