I agree! I also wonder why the code does not include the correct identification of the cable being discussed here! the code should a -B everywhere that the NM, NMC, and NMS cable is mentioned in the code, and there are hundreds.
Another issue I have with the code panels!
They don't want to accept my proposals because it would create too much work for everyone who writes catalogs and other documents.
PS: If you have saved any of the old BX and can take some close up pictures, send them to me and I will post them here for us to see.
Joe Tedesco, NEC Consultant