Is there not a Scottish play, a theatre piece, called The Silver Darlings, as well? Maybe named after the song, maybe just named after the saying.
I seem to recall reading about Raindogs, the theatre company founded by the likes of Robert Carlyle in Glasgow, staging a production years ago of The Silver Darlings.
First I had heard of the term.
I wonder if dimplydoo dimple and nutty are no longer with us.