This is not what someone thinks is the cannon, this is the cannon. When an orbital drydock is described as a federation fleetyard, then that strongly implies that these ships are built in orbit. When federation starships are depicted as being launched from and undergoing major overhauls in orbital drydocks it also demonstrates that these ships are built in space.
Which still does nothing to contradict the E being built on Earth. Examples; Enterprise D: Built in Orbit of Mars (shown in at least one episode), 1701: building never shown (refit done in spacedock), C: Never Shown, B: Never shown, A: never shown. "Strongly implied" to be canon is not the same as "canon" no matter how hard you pretend.
Considering the scale of the TMP refit, if the ships were initially built planetside they would have landed it common sense.
If ships were built planetside, landing would be a routine manuver- Star Trek voyager states its not
also the B was built in space, if it was built on land, they would not have had to launch the champagne bottle at it in Generations. I don't have to pretend anything. the facts speak for themselves, unfortunately the makers of the current movie didn't bother to listen. And then they had to be incredible *&%^&*bags about it. Also, if you want to insult me again, send me your name and address. It is easy for people like you to be brave by insulting people on an anonymous forum, but if you are going to do this, at least be ready to say it to my face.
Where you are making your judgment on is that Voyager is early 24th century, TNG is late 23 century and is about 110 years after the big E first launched.
The dedication plaque states San Francisco Shipyards .. Hmmm Alameda maybe, the Naval base.. remember "The Voyage Home", think of Kirks reaction when Checkov told him that the Naval Yards had the Enterprise in it.. Hmmm.. maybe that is where the idea came from.. turn the Naval yards at Alameda into a construction site for the CA class ships.. Heck that is where Battleships were constructed and more ship being constructed and repaired there today.. namely Aircraft Carriers.. given that bit of information.. the original Enterprise of the Constitution class was 288 Meters long or 944.88 feet.. the USS Enterprise that is a Nuclear Air Craft Carrier is 1,123 feet making her the longest naval vessel in the world, built in San Francisco Bay in Alameda.. the Fanology behind this was that the parts of the Enterprise is built on earth and then assembled in orbit in order to reduce the cost and time of making multiple deliveries since transporters still had problems and were not truly reliable...
Abrams is not violating canon.. he is confirming popular fandom into canon where none existed before.
Enterprise depicted NX class ships being built in orbit. So you're suggesting that starfleet basically built ships in orbit in the 22nd century, stopped building them in orbit for some reason in the 23rd century, and then started building them in orbit again in the 24th century? I thought the ships being built above San Francisco had to do with the fact that starfleet headquarters is located there. Although the purpose of the dedication plaque in 1966 was to connect the Enterprise with something the audience would be familiar with like a major US city.
Being built in space can be constituted as assembly of the parts. However the parts have to be made some where.. It would be more cost effective to build the parts on Earth and then transport large pieces into orbit for assembly, thus being built in space.
If the whole ship was being built in space, there would be massive traffic to and from the facility and the transport lanes would get congested fast since material replicators at that time did not exist.
The NX-01, if you consider it a canon ship,
(See Star Trek: The Motion Picture for the Enterprise XVC-330, the ship before the NCC-1701.. NX-01 is not a canon ship according to Roddenberry's time line and was used as a ratings grabber by B&B .. It only gets canon credit for being on screen since B&B's budget was small, they took the Akira class ship and flipped the secondary hull upside down and painted it golden brown instead of sticking with previously established canon) ,
could have been built on the ground piece by piece, and then built in space from the pieces that they made on Earth. Same thing goes for the NCC-1701 .. the NCC-1701 was a complete refit done in space.. but the parts were built on the ground and the saucer was complete rebuilt on the ground (Reference the book 'Flag Full Of Stars') and then flown by Kirk to be attached to the secondary hull at Starbase001.
There has to be a starting point.. like the super structure.. I can see it now.. 0 G environment and trying to weld the structure together and someone sneezes and bumps the beam.. how it takes an hour to reposition the piece when on earth, Gravity would work as an anchor point on one end and allow control over the structure to be more precise.
Think about the efficiency of the project in a time before replicators and huge transporter complexes .. Assembly would be 100 times more efficient on Earth during the time when the NCC-1701 was being built than it would be in space.. Where in TNG, Technology advanced 110 years and they have a hullava lot better transporters, and now matter replicators, precision point tractors, etc which would make building a ship from scratch in space much more feasible than it would have been when Kirk was a teenager during the time that the Enterprise was being built.
Just like people don't realize that Pike was not the first captain of the Big E, Robert April was (reference Gene Roddenberry's Star Trek : The Animated Adventures), then Pike, then Kirk.. There was 19 to 20 years from when the big E launched to where Kirk took command of her.. That means when the Enterprise first launched, kirk was between the ages of 13 to 16 (can't remember off the top of my head) and had not yet entered Starfleet.
So if you are going back that far, then it is not unreasonable to conclude that the Enterprise was built on Earth and then assembeled in space, which would be the most cost efficient way to do it at that time.