Nimoy was actually involved in developing and writing Spock's TMP story, so I think he would have been quite conscisous of it. A quote I posted in an
earlier thread:
"Harold and I worked closely on the script as we went along. I am pleased with what we worked on that is in the film, but I'm not convinced that they have successfully used everything that we worked on. [...] I felt we included ideas which I'm not sure are resonating now in the film. For example, the very last line that i have in the film where I say my work on Vulcan is complete: that line I don't think really tells us what it should. It seems to be a gratuitous, arbitrary decision on Spock's part. Whereas the concept -- and the design of the script -- was that Spock would come aboard the ship intending to find some answers to a problem that he was trying to deal with on Vulcan. It was a personal search, a kind of evolutionary experience that he went to Vulcan to accomplish, but couldn't achieve there. He hopes that the answers to these questions that are troubling him will be available to him when he gets to V'Ger, this thinking, being mind out in space.
"Now when he gets there, it's another matter. As he says to Kirk in sickbay, it doesn't have any answers. He says 'I should have known,' the irony is there, 'V'Ger doesn't have any answers, it's asking questions.' Now , the point here is -- and it's unfortunate that I have to explain it, it's like trying to explain a painting; either it works or it doesn't -- that what we were after was that Spock has discovered that the search is unnecessary."
--Leonard Nimoy, quoted in Return to Tomorrow: The Filming of Star Trek the Motion Picture by Preston Neal Jones