Guest, Ed. From what leeneia said, she couldn't identify the specific tune called The Cuckoo's Nest which was being referred to, so she was not dismissing it as a candidate.

"From: leeneia - PM
"Date: 18 Mar 16 - 07:22 PM

"I recently went to the abc tunefinder for versions of the Cuckoo's Nest, and I stopped at 139 of them. True, some of them were the same. Nonetheless, identifying a tune as The Cuckoo's Nest is no help."

When comparing tunes, I find it very difficult to just listen to the tunes. I need to see the dots.

When I listened again to the fairy garden tune, it just seemed to be an arrangement of notes in chords from a fairly common chord progression which could compare the tune to many different tunes with a similar chord progression. My personal take on the quest is that ad people are unlikely to listen to folk music, so on probability alone, they are more likely to poach tunes from pop than folk. But that's just me surmising about ad people. No basis in fact at all. (Ad people are very low on the food chain, in my estimation. Sorry for any offence, if you are one.)

I could hear more similarity in Martin Carthy's version than the one recorded in a pub.

Maybe, Eliza, you can now rest easy. Until the next earworm hits you.

My latest earworm is Westering Home.

Helen