If you ascribe to Trek's age old policy of "what happens on screen, is canon", then like @RedDwarf said, the evolutionary history of the Constitution class is now something like this:
It's getting silly, but for those of us who grew up with the Encyclopedia, or the many people who construct models and love the starship aspect of fandom, I guess it's not impossible they are the same design being refit several times, even if highly implausible by today's standard.
For those here who don't know, there was already a difference between Pike's Enterprise and Kirk's, which we generally attribute to a refit. I guess maybe it underwent another one in between.




It's getting silly, but for those of us who grew up with the Encyclopedia, or the many people who construct models and love the starship aspect of fandom, I guess it's not impossible they are the same design being refit several times, even if highly implausible by today's standard.




For those here who don't know, there was already a difference between Pike's Enterprise and Kirk's, which we generally attribute to a refit. I guess maybe it underwent another one in between.