Originally Posted by That Metal Beastie
It was both intentional and not. The emotions Spock displayed early on were certainly written and performed that way intentionally. And yes, it was decided a little later he showed no emotions because Vulcans had no emotions. Then later it was decided that Spock, being half human, did have emotions but with rigid Vulcan control surpressed and controlled them.
It was not that Nimoy didn't have a handle on the character but that the creators- producers, writers and Nimoy- were still in the process of developing and nailing down the character of Mr. Spock.
That all was 'taken as canon' because that's how was canon developed and established. It was determined decades ago that 'if it was on the screen, it was canon'. And that's been (for the most part) true for these decades. And when something presented on screen seemed to contradict canon, explainations for these apparent canon violations were contrived. And were often, if not usually, satisfying. And THAT my friend has been the pleasure and pain of Trek canon.
What JJ, Orci and Kurtzman did was look at the early 'emotional', developing Spock performances and gave them a canonical(?) explaination. Brilliant and satisfying, IMO.
I discovered an interesting passage in Nimoy's I AM SPOCK,
"Spock's "hypnotic" looks strongly affects Earth females and he goes to great pains too avoid too much contact with them. There is a back story on this-many years ago when Mr. Spock first joined the service, he was careless on this score, perhaps even enjoyed this strange ability over Earth women. But it quickly created both personal and professional troubles."
This is taken from a May 1966 memo to Nimoy by Roddenberry on the Spock character, unofficial. But it seems to leave open the opportunity for a backstory involving Spock and a romantic relationship with an Earth female he had a professional relationship. But no specific mention of Uhura, and if a relationship between the two had been in the characters' backstory, it definately would have made itself felt in the early episodes of TOS.