That's nonsense, no referee gets to that level without knowing law inside out. Especially these days where just about every training seminar starts with a LoTG exam. There's a huge difference though between not knowing law and knowing it but making the wrong decision when put on the spot. That's why there are thousands of electrical accidents every year, the electricians know the regs and are qualified in them, but just make mistakes, just as referees know the laws but make mistakes.