"Regarding "audiences joining in" - I've always been opposed to this happening on anything other than choruses, unless invited."

I remember a night in a Manchester folk club in the 1980s, when a well-known professional performer (still working to this day) got so exasperated with an audience member on the front row singing along with everything, just slightly out of time, that he broke off the song in mid-verse to shout: "Will you fucking SHUT UP!"

Loving 'Sir Olaf'; Wicker Man staged at The Hacienda is a good start, but you're channelling Gong, Hedningarna and the Incredible String Band as well. Quite a feat.