The way Raggytash described the event, people were not playing as individuals: "The session in question was a take-your-turn session, but as always with such sessions, if someone played a tune, e.g. on accordion, several others joined in on diverse musical instruments."

If, in sessions like this, Raggytash (or anyone else with this problem) wants to "get someone to stop without offending them", I think he would have to stop *everyone* from starting to accompany him in the first place. When it came to his turn to start a tune or song, he would have to say: "I know you're all playing/singing along with all the other tunes, but for my turn, I am going to play/sing XYZ on my own," and his would be a solo performance each time his turn came round. The only fair thing to do then, of course, would be for him to refrain from playing/singing along with any of the other people when it was their turn to start a tune !

I think you have to make a choice of either saying "My turns are always solos" or welcoming all-comers and being an all-comer yourself. There are consequences that you have to be prepared to accept, whichever option you choose ;)

- jeanie