Are we over complicating this?

I personally have never viewed singarounds as performance, but are more about self entertainment, a group of (hopefully) like minded people singing and playing for the pure pleasure of doing it.

The singarounds I've attended have always been friendly, welcoming and inclusive, if someone is not of a particularly good standard, or needs to use a cheat sheet or whatever, that's not an issue as they are not 'performing', they are 'taking part'.

A 'performance' is a different matter altogether, where one is 'playing' to an audience, who have probably paid for the privilege of being there, I would expect, even at an amateur level, that the 'performance' had been rehearsed and the material properly learned.