I have read that script to. And knowing what I know about TV? That would not have been the final shooting script. The pictures that are in my PHASE TWO book are all the proof I need; that show would have blew chunks. It would have been very much like season 1 of TNG. TNG, despite what some people believe, was just PHASE TWO updated. Either version would have suffered because of who was running them; Gene Roddenberry. And back in 1975, or whatever, Roddenberry would have been younger and would have been given more time to make it work; but he was already the problem.
Harve Benette, Nick Meyer, pretty much saved TREK. The principle actors, Shatner - Nimoy, seem to agree. And TNG was heading down the path of oblivion until Roddenberry gave up control to Berman.
Had there been no 'evil' Harve, then there would not have been the success of VOYAGE HOME which gave TNG birth.
I would agree that Harve Bennet et al saved Trek from TMP (which I also know was born from Phase II). However, as you point out, the stuff in the Phase II book would not have been the final shooting scripts. Who knows how they would have developed.
What about the Phase II pictures suggests to you that the show would blow chunks?