On a related note... I recently came unstuck singing the version of 'Twankydillo' that I learned from the New Penguin Book of English Folk Songs. The chorus in that book has a slightly different melody to the one everyone seems to know.

It's not radically different, but it's different enough for it to cause a bit of a car-crash: everybody in the room tried to join in, everyone got confused! I adapted and sang all the other choruses the way everyone else wanted to sing them. On the one hand, I felt people should have listened to what I was singing; on the other hand, it's a big anthemic chorus song, it's a singaround, so it's kind of anti-social not to sing it the way the Coppers did, the way everyone knows!

When I've sung that song at subsequent singarounds, I've given up on the New Penguin chorus and stuck to the Copper Family chorus.