GM/Toyota/NUUMI would produce four times vehicles in the same amount of time in that plant. (about 120 to 130k/quarter, depending on the nuumi production numbers you believe)
Maybe. Some of the production process is brilliant. At the same time, some of it is far less sophisticated than you might imagine from much publicized reports. And they have skeletons, alright.
It has been reported that Tesla makes a lot of thier own parts. So more of the total supply chain for manufacturing the car exists in that plant.
For example Tesla manufacturers thier own motor in the plant were the NUMMI plant would have had thier ICE motors pre-assembled.