Well I guess we’ve all been there - those of us that play in sessions that is - those of the spontaneous sort (no set lists,, music stands, sheet music, etc). There’s a wee hiatus between tunes (unusually) so you start into one of your favourite tunes - no, it’s not one that you or a friend just wrote yesterday. It’s one you thought everyone would know - but they don’t! So do you plough on regardless, hoping you’ll get it right, continue what has now become your solo performance, hoping fervently that they’ll all be desperate to know what that tune was and how can they get the dots or a recording of it to learn it, or do you just fizzle out and stop playing, or offer to play something else? Or do you always ask before you play a tune - does anyone know Joe Bloggs’s Old Boots?