"I think it must depend how you define the folk world. I can't see Des O'Connor doing the LP, or the Bachelors (even)."

What I meant was that all three of those titles were available - for example - in the Daily Express Community Song Book, which would have been an obvious place to go looking for folk songs as templates for parody, even if the writer didn't know them already. You'd have been unlikely, I suspect, to have heard those songs in the folk club movement, where they would have been considered old hat. Another of Rambling Sid's songs is based on 'The Foggy Dew' which would have been familiar from the Britten arrangement.

I'd love to have heard The Bachelors' album of made-up yokelisms and outrageously naughty double-entendres, though.