I was sitting in a session in Oslo a few years back...no names mentioned, as to the venue...but someone asked me to do John Martyn's 'I don't want to know about evil'.
Dezy, my mate, who is a trad flute player, but well known for his forays into Ian Anderson country, came in somewhere in the middle of the 2nd verse, accompanied by this other cove, who insisted on putting an A7 in everywhere I was putting the proper AMINOR7 in. He also exaggerated the rhythm; playing, as he was with one of those awful three cornered plectrums, that turned every stroke into a declaration of war.

Having people join in, is fine; and Dezy hadn't heard the song before.
But he LISTENED to what was going on, and tempered his playing to suit.

I eventually had to stop, because the unaestheticism of it all, got to me in the end.

B.