You really need to back up and read the scope of 300.6 before we start nitpicking the language. Lets start over.
300.6 Protection Against Corrosion.
Metal raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, fittings, supports, and support hardware shall be of materials suitable for the environment in which they are to be installed.
It doesn't even sound like we care what 300.6 says if we use a plastic wiring method
