I am happy it raised your interest. I have to be honest, I didn't even considered the use case you mentioned in your toot.
I haven't tested it yet, but from what I can read in the docs, Resource classes don't have a flag you can use during "duplicate()" related to signals, the same way Nodes do.
And since the signal is not exported, I assume it will just create a new signal with no connections on the copied resource.