Yeah, but that was Spock speaking after becoming, as he viewed it, a teacher, and further indicating that in an "actual duty" situation, the senior officer on board must assume command. Plus, he was making an argument designed to ease Kirk's potential conflicted feelings about taking command. Several years later, he has absolutely no problem taking command, and quite skillfully, in TUC.
In some episodes of TOS, Spock is a talented commander who makes reasoned decisions and earns the respect of his subordinates. "Who Mourns for Adonais" is perhaps the best example of this, but there are several others ("The Mark of Gideon" comes to mind). But in other episodes, he's closed off ("The Paradise Syndrome") or downright strange (as in "That Which Survives").
So it's quite inconsistent. The producers did a far better job consistently portraying Scotty as an apt starship commander than they did Spock.
