Here's the dilemna: 300-4d of the NEC requires protection of NM sheathed cable and MC cable within 1/1/4" of the edge of a stud where the conductors are LIKELY to be penetrated. The local AHJ's are requiring nail plates behind the conductors on a 3-1/2" stud wall where the non-metallic sheathed cable enters a plastic box in a typical residence. I hope you got that. In other words, not only where a cable is perpindicular to a stud and the clearance is less than 1-1/4", but also where the cable enters the box, because this space could be as little as 1/4". The inspectors are reading the intent in the 99 handbook and not the literal sense of the word. Is anybody in the country having to protect the back of a box where the cable enters it with nail plates and does anybody agree with this? Please respond to this. Florida enforces only the 1999 NEC with no exceptions in accordance with the Florida Building Code.
I have heard some good ones, but that one will go on my top ten. What's next, RMC for residential. Gimme a break. Perhaps you might want to run some stud guards across the breakers too, just incase they decide to hang a picture there.
I'm here, and have wondered about this very thing myself, but have never heard of additional protection being required by anyone. Perhaps you could send the Manufacturers an email and ask them why they put the holes where they do. I think we'd all be interested in hearing the answer if you get one.