I have no idea how Elon Musk rolls out so many launches in quick succession. I’m guessing ABSENCE OF BUREAUCRATIC BULLSH!T has a lot to do with it.
Seems he views regulations as just part of the engineering problem.
Hence he’s building massive reusable rockets in tents on a beach in Texas.
Methinks: once he figured out stainless steel was a viable material for rockets, it just turned into an outdoor industrial manufacturing project - no clean rooms needed. Heck, they’re supposed to work on the rough environments of Mars & Moon, why not build ‘em that way? dirt & weather shouldn’t adversely affect them in use, so just bake that in.