I too have bonded a plastic exit sign. (Whatever you want Detroit.)
Its like, yes these boxes are within 1.25" and a screw could go threw it. The number of times this occurs is low. Do we need to spend $$$,$$$, to try and save $$?
I guess a whole new product needs to be created to meet code.
A rule like this hinders our ability to do excellent work.
Eg. Nicer homes we will tend to use 20cube boxes. This just gives us room for anything. Dimmer, gfci, nightlight, fan control... it does not matter, we have room. The tiny box upgrade costs pennies.
Now if I wanted to do that... metal boxes or nail plates. Now I'm doing this for dollars.
Simple, clean, quality would be too easy for us. Lets muck it up. Probably push this into the 2017 code book.
