At least he didn't say, "It's been fun."
I think the reason Spock said, "Understood" is because it was all 6 plus probably one or two more that we didn't list. Spock and Kirk worked well together.
That's one thing I've always favored Kirk over the other captains, at least the ones I've watched, that a really formal typer person like Spock can call him Jim and it's not forced or strange in any way. Every other time, imo, someone tried to address their captain by their name it sounded so forced and just goofy. Kirk's officers really would follow him to the gates of hell, they were his friends as well as his underlings and he didn't lord over them. All the senior officers called him by his first name, Jim, and even when the junior officers say Captain, they seem to say it with a possesiveness like it's more than just a rank.
Sorry for my indulgence, I really love this show.
Scotty called him Jim that one time in Mirror, Mirror, which was just one of those moments that made the show what it was.
