Here's one that's easy, since Grace Lee Whitney addresses the Solow/Justman book directly in her own memoir:
When casting was discussed with Gene, the only performers he would stand up for were the actresses with whom he'd had a previous personal relationship: Majel Barrett Nichelle Nichols and Grace Lee Whitney.
--Herb Solow, Inside Star Trek: The Real Story (1996), p.75
Barrett's relationship with Roddenberry is, of course, well known; Nichols' relationship with him is described extensively in the Solow/Justman book, as well as her own memoir. But Whitney flat out denies having any kind of relationship with Roddenberry:
...I never had a romantic relationship with Gene Roddenberry before Star Trek, during Star Trek, or after Star Trek. In fact, before I started working with him on Star Trek, I scarcely knew him in any way that could even be remotely defined as 'personal.'
--Grace Lee Whitney (with Jim Denney), The Longest Trek: My Tour of the Galaxy (1998), p.73
I'm slowly listening through the tremendous La-La Land set of the show's original scores, but perhaps someone who is more familiar with the music can tell me if this anecdote lines up with the music on the set:
Business Affairs had prepared a rerun cost schedule indicating who must be paid additional money every time an episode was repeated. It was pointed out that while no musicians would receive rerun fees under the agreement with the American Federation of Musicians, the soprano singer, Loulie Jean Norman, having been hired under a Screen Actors Guild agreement, had to be treated as an actress. She would receive rerun fees.
The money was small, but the issue was huge. If money could be saved for the rest of Star Trek's life by replacing a human sound with an electronic sound, why shouldn't a reasonable management make the change? It was a good argument.
I called [Robert Justman] and told him not to hire the soprano again for the new [second] season. He wasn't happy, but the change was made. Since Sandy Courage never watched the series after the first season, he was totally unaware of the change until we informed him twenty-seven years later.
--Herb Solow, Inside Star Trek: The Real Story (1996), p.351-352
I have the feeling that this is another story that is the result of a hazy memory. The La-La Land set definitely indicates that Norman recorded the main title with Alexander Courage for the second season, during the sessions in which he recorded 30 minutes of library music (although I suppose that doesn't mean it was used, although a wasted recording seems unlikely given how cost-conscious the series was). I know an electric violin version was recorded and used -- but during the early part of the first season, not later as a cost-saving measure.
Could someone with more comprehensive knowledge of the music shed some light on this?