There are a lot of instances here in Chicago of Code items that were adopted to head off that 'once in a blue moon' incident from reoccuring or to protect folks from their own stupidity, but there are also a lot of things that make sense.
The requirement for EMT means that it's a WHOLE lot harder to poke a nail through a conductor; also, if the insulation gets nicked or fails the conductor will short to the metallic raceway and immediately trip the breaker.
It's also quicker to repair. Pulling out the wires and pulling new ones in is significantly quicker than ripping up wallboard to replace NM cable.
And yes...I will grant you that some of our Code items have interesting histories.
