Scat Tester in Susex played his music one way, Black Umfolosi did it their way, Mongloian goatherds do it their way. How could they possibly come up with a common form? Don't be silly.

I don't ordinary draw attention to typos (God knows I make enough of them myself!) but can we really let Scat Tester pass without a chuckle? Especially as N & T are quite separate on a QWERTY keyboard. A Freudian slip of the finger perhaps? Or one of the more picturesque rural trades now lost to agrarian mechanisation. Oo-Ar, I be a scat tester, I be - just like my father afore me, and his father afore him - scat testers for generations... A thankless task no doubt, but one that at least paid well enough to keep the fellow up in concertina repairs...

Looking around for Scan Tester (on WIKI; nothing on YouTube) we learn he was nicknamed Scantelope art the age of 5; the only other reference for Scantelope is Scantelope - a fleet-of-foot, bare-all buxom beast (whose revealing exploits are chronicled in the best-selling naturist book, “What Really Went On Behind the Scenes in the Garden of Eden”). One might ponder in the hope of enlightenment...

But, as I said earlier, Greg, I was talking of English Folk Song and Ballad which, as with any music, is as much about Form as it is about Derivation. Once more I apologise for not making this clear at the time. Anyway - in each of the examples you cite Form is the equal at least (let's be generous here) of Derivation - not the same Form I grant, nor yet even the same Derivation (let's be grateful for diversity, eh?), but Form nevertheless, which is itself derived, whatever the Idiom. Indeed one might see the Form as the defining aspect of a particular tradition. Worth a thought anyway?

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I'm niggled this morning because on reading my copy of I, Claudius earlier there was a mention of simnel cakes (Penguin Modern Classics, 2006; Chapter 9, p 107). It's really too early to get my head around it, but I noticed in one of our Lancastrian Garden Centres the other day Simnel Cakes are now being sold as Spring Cakes. Indeed, even Easter is fast vanishing under a wave of secular neo-paganism...