Nothing substantiates that in regards to SF ships of the same class that leave construction yards.
AND NOTHING SUBSTANTIATES THAT
OPINION ANY MORE THAN MINE.
And a *sigh* back atcha pal. I don't know why you're taking this so seriously, we're just postulating fiction that has no canon referent whatsoever. Neither of us is correct OR wrong, both our opinions are equally as likely. I'm just throwing out a "what if" thought process here. Although you seem to be working from assumptions that the real world doesn't support.
The five space shuttle orbiters were each substantially different from the other. While some parts were interchangeable, a LOT were not. No SR-71's instrument panel was identical to another's. No Nimitz Class carrier is 100% the same as the previous build. Etc, etc...
Some of the hypothetical variations on the GC I mention that you casually dismiss with refitting would require such extreme rework that it would be pointless. Say the main EPS interconnect trunk on ship 4 is moved 50 meters to port simply because some engineer realized a handier way to route it to make final assembly at the shipyard easier. This in no way invalidates the current position of the trunk on ships 1 thru 3, because they're already assembled, and rerouting the trunk would be expensive and pointless, not unlike this thread. All the ships work fine, but that leaves 4 thru 6's saucers unable to interchange with 1 thru 3's - an operation that Starfleet considers so unlikely anyway, as to eliminate any point in modifying the older ships.
I await your next rude attempt to treat me like an ignorant child.
My post was not written in an attempt to insult anyone nor was I treating you as an 'ignorant child'.
If my post insulted you in some way, then I apologize.
I would like to make a suggestion that you do not jump to conclusions in ascertaining how I treat others simply based on what is written due to the fact that textual information or description of events/situations (and whatnot) is not always a representation of the writer's present frame of mind or how they perceive others (unless it's explicitly stated/confirmed by the same poster/writer).
As for your opinion on everything else, ... we will just agree to disagree.
I leave an open mind to the possibility that what you say may be accurate and what I say may be incorrect ... but same goes vice versa.
A little reminder of which we are all aware of: SF is a fictional organization with technological capability surpassing our own by almost 300 years (and having contact with alien races that were in space for over 1000 years before humans in that fictional reality).
While some aspects of it's technology and how things are done will be vaguely similar to our own, you cannot expect everything to be the same and operate in a way you imagine.
Like I said, I leave an open mind to the possibility you may be correct, but I also do the same for myself.
When it comes to Trek, I primarily operate on what was witnessed on-screen and apply some logic (along with theoretical possibilities subject to change).
I don't apply contemporary real-life examples all the time of how things are done when it comes to design and construction of fictional star-ships because WE don't make star-ships that are warp capable, have warp cores, replicators and computers so advanced that would put anything we dish out (and potentially for some time to come) to shame.
So taking into consideration everything I said, there is enough to theoretically support my own claim that all ships of the same class leave construction yards identical (ending up with minute changes in how a ship operates based on each crew customizing it to their own needs and wants in the field), and that ships of the same class which have been constructed at an earlier time would be re-fitted to accommodate any design changes that SF might include as time passes.
As for your point that SF would not consider modification or re-fit (including extensive design alterations) is easily disputed through an example of transition of TOS to TMP and various examples from on-screen evidence.
The 1701 original was re-fitted extensively resulting in design changes (while retaining the basic aspect of the TOS version) which encompassed both external and internal changes.
Having said that, I do not think that SF would consider modification of older ships 'unlikely'.
Deks... just to put matters into perspective (and I'm not CHALLENGING you here... just askin')...
Would you mind telling us a little bit more about yourself? There are a number of folks who post regularly in this forum who have a massive amount of real-world knowledge about naval vessels (far more than I do... I'm an aerospace guy!).
Suffice to say that I'm an artist with interests, skills and knowledge in various fields (incl. computers) and that my own knowledge of real-naval vessels is limited.
To that effect, I will repeat what I stated before, I don't think applying examples of how things are done in real-life are applicable to Trek all the time.
You speak as though you believe you have a claim to being an "authority." Just to put matters into perspective, I'd personally like to know a little more about who you are. (and the same goes for the rest of you guys... except for those of you who I already know... but feel free to chime in for those here who DON'T know ya!)
Slight alteration: I don't 'believe' (any aspect/version of that word doesn't exist in my vocabulary).
I never stated of having an 'authority' of any kind.
If you arrived to such a conclusion because of what I wrote, then it's your personal assumption/interpretation.
As stated earlier, I merely wrote my own opinion on the subject matter based on what we saw on-screen and using some logical deduction while not necessarily applying real-life examples (which would essentially be pointless most of the time when it comes to Trek).