Re: How do you account for the drastic design change between TOS and T
No, because Tactical and Security are normally the same thing in Trek, and they'd both wear gold. Worf was the bridge watch officer in the first season. He was basically responsible for commanding the bridge when the senior officers were away (though this was really only seen in the pilot) or filling in at any unmanned station as needed.
I think he was the Tactical Officer in Season 1 of TNG and switch to the gold uniform on TNG when he took over Yar's position as head of Security.
No, because Tactical and Security are normally the same thing in Trek, and they'd both wear gold. Worf was the bridge watch officer in the first season. He was basically responsible for commanding the bridge when the senior officers were away (though this was really only seen in the pilot) or filling in at any unmanned station as needed.