Maybe the Receptacle and Cover Manufacturers need to develope a Receptacle and Cover just for this type of installation.
The Receptacle yoke could have 2 addtional tapped holes in it like a switch but leave the center tapped hole in the receptacle just as it is.
Design a Stainless Receptacle cover with 3 holes in it instead of just one and problem solved for everyone.
Regardless whether the center screw of the cover, was used to secure a wall wart, came loose, or even went mising, it wouldnt fall down since it still would had the other 2, and the grounding wouldnt be comprimised either.
I'll be waiting on my royalty check whenever Pass Seymour, levtion, or someone like that decides to put such a great idea into play....
JAP>