Have you seen Richard Thomas in The Americans? I swear the man has a portrait in his attic that's doing his aging for him . . . .
I've forgotten what it was I saw him, in, Mr. Cox, but I think you're on to something about the portrait: I couldn't believe how good he looked!
Chapel is actually missing for most of the second season of TAS. IIRC, this is when Majel Barrett was due to give birth to her son, Rod. (She does one Chapel episode and one M'Ress episode only.) But Dr Chapel could have then "returned to the Enterprise to serve as McCoy's associate" before McCoy left the ship. "In Thy Image" begins McCoy's arc with him as a vet on Earth, and Kirk having to take Dr Chapel off her previous assignment because he can't get McCoy back as Chief Surgeon. McCoy being drafted back into Starfleet by Kirk is similarly scripted in ITI and TMP.
It always seemed odd to me that Kirk assumed he'd be returning to command Enterprise after repairs were completed. In The Wrath of Khan, Enterprise is under the command of Spock and is just a training ship.
I think he's talking about The Search for Spock. Kirk and Scotty assumed that Enterprise would be refitted after the damage she sustained due to the Reliant attacks. Admiral Morrow told them otherwise and refused Kirk's request that he be allowed to take the ship to Genesis to retrieve Spock. The Enterprise was under Spock's command in TWOK because the vessel was undertaking a training cruise. Kirk assumed command once the ship went on actual duty due to the Regula I emergency. It's my understanding- and Christopher detailed this in one of his novels- that the Enterprise was under Spock's command for training missions but that as Commandant of Starfleet Academy, Kirk used the vessel as his flagship when he was aboard or when the ship was assigned to regular missions; therefore, Kirk remained in command after Spock's death because Enterprise was still on active duty following the incident with Khan. --Sran
I don't know whether Christopher based his book on something "official" or if he just went off of his own bat, but I can tell you that this is not the tonality of what's in the actual STAR TREK II movie. It's very apparent and abundantly clear that Kirk is a visiting dignitary and that's it. He has no claim on this ship, other than usurping it from Spock, which he initially resists doing, until Spock steps down, voluntarily. This "Kirk was always in command, except on training cruises" spin doesn't really even fly.
As no one said that, I'm not sure what point you're trying to make. The Enterprise was assigned to Starfleet Academy, so Spock was its primary commanding officer. In the event that the vessel went on actual duty, Kirk assumed command- something that was clearly the exception rather than the rule. --Sran