The interesting thing here is that the Excelsior
was in production before transwarp had been tested - namely, NX-2000 had been completed. Not just thrown together to perform experiments on transwarp, but completed
. As in, she even had all her guns fitted.
What is singularly uninteresting is the fate of the former crew of the Yorktown
. It just isn't relevant or realistic to worry about what happens to the "former crew" of a starship; in the real world, no such thing even exists, and personnel are constantly being shuffled between vessels and other assignments. If the skipper of the Yorktown
is told to move to another assignment because Kirk needs his or her ship, and he or she complains, that only goes to show that he or she is not fit to serve in Starfleet. Or in any real-world military at least. Or basically any other real-world organization, for that matter.
*When the Galaxy-class Enterprise launched, we have no idea how long the U.S.S. Galaxy had been in service nor do we know how long her trial runs were.
Yet the skippers of both USS Enterprise
and USS Yamato
were convinced that the class could still be a complete dud as late as the start of the second season of TNG, in "Contagion".
It's not particularly rare to build major ships in batches without allocating any time for testing. If you wait for the Bismarck
to finish trial runs before you commit to building the Tirpitz
, you have already lost everything because the second ship will certainly be outdated by the time of her launching, and the subcontractors who worked on the first ship will have lost their special expertise and supplies in the meantime, immensely increasing the expenses. It's much better to build four duds, reaping the full benefits of "mass" (or at least optimally synchronized) production, and then simultaneously fix them all if and when the need arises.