No idea. It sounds as though double barreled shotguns would be illegal if they fired both barrels with the pull of one trigger, but most such shotguns either have two triggers or can only fire one barrel at a time. The 1911 is even more fuzzy--you can get it with two triggers and independent sears, or with the triggers welded together and separate sear groups.
I feel like the BATF wouldn't throw the book at you for either one since the intent of the regulation is surely to prevent automatic weapons fire as opposed to simultaneous multibarrel fire... but on the other hand, it's the BATF.