When I was living in the Midwest, the traffic lights were synced to the local GM plant's shift schedule because the volume of employees driving in made it look like traffic to a theme park. Does Tesla's factory do something similar?
The thing that impressed me most was that the shell would be assembled for painting, then the doors would go off on their merry way and rejoin the same car hours later right before the final checks so that the paint would exactly match.
Lateish edit
I forgot to add, all of those crazy robots in the Tesla videos that assemble the vehicles without human intervention? Other manufacturers have relied on those for at least a decade.. It was generally considered proprietary which is why it seemed so novel when Tesla released their promo videos.
Production line design and tuning is all about cycle time. The line runs at the speed of the slowest station. Any operation that takes too long has to be broken up into successive operations, even if one station could do it. You can fan out the line to multiple stations if you absolutely have to have a long cycle, but that adds cost, takes up floor space, and is really tough to retrofit. It's not unusual, though, to redesign the slowest station if that will speed up the whole line.
Take a look at that Mercedes assembly line. Note all the custom fixtures required, many with sensor and actuators attached. All those have to be designed, built, tested, and run through enough cycles that they behave reliably. One failure stops the whole line.
Previous reports seem to indicate that the workers may be at the factory for 20 hours a day, so perhaps they're all sleeping next to Elon in burlap sacks to cut down on congestion?
[0] https://www.google.com/maps/@39.5375576,-119.4397724,14.46z/...
https://www.google.com/maps/place/Letsby+Ave,+Sheffield,+Sou...
Explanation for anyone similarly baffled:
http://forum.wordreference.com/threads/999-letsby-avenue.147...