But while there are some overall design stylings that Taylor retained—no doubt due to the myriad conversations with RA&A and Roddenberry, et al. when they did the big review of the miniatures and designs when it shifted from planned t.v. show to motion picture—I think many people (myself included at first) under-appreciate that the TMP-refit was a Taylor led design. Others both at Astra Image and Magicam were certainly involved and no one person can claim credit of the re-design (Probert, Stetson, Dow), but at the end of the day the bulk of it was done under Taylor’s design direction and was simply a continuation and modification of Phase II design. Though there are obvious main aspects of it that were retained such as the integrated deflection dish, through-neck torpedo launchers, etc.
Taylor started (according to him) his redesign with the baseline of the edict from Roddenberry of an even 1,000 feet length overall, and the design of the various main elements (saucer, nacelle, secondary hull) where worked out within that LOA and the proportions made in relation to each other, etc.