CW: What he is describing would work (though I hesitate to recommend it).
The reason that it works is that the wire in your electrical ground is so long
that it is effectively not grounded at HF frequencies and will not ground out
the signal.

I can't disagree with any of that. :-)

I'm sure signals picked up by the hot lines would inductively couple to the
proximal ground wire.

I do recommend disconnecting from the socket ground when there is a
thunderstorm in the area. A good jolt could also come in on that ground.

Too, I'm assuming the ground terminal is properly wired. Normally, that's
pretty hard for any one to get screwed up. I have seen, though, polarized
two-pin sockets wired in reverse. Of course, today's the hot and neutral pins
of today's three-pin socket is polarized. That could still be wired in reverse,
especially if the socket is controlled by a switch.

To put it in perspective, though, for the carrier current operation that I did
during WWII, the transmitter and receiver were capacity coupled to the hot and
neutral wires. LOL

Bill, K5BY