Is a concert something you receive, or something you give? Dion has turned down tickets on the basis of the crowd alone, which raises the question of whether the people around you are part of the experience or an obstacle to it. Christian thinks a room singing together is the whole point. Josh thinks you paid for a service. Somewhere in there is a price at which a cultural obligation becomes negotiable.

Then the harder dilemma: you're on a dance floor, the sing-along has turned personal, people are making eye contact - and you know roughly thirty per cent of the words. Do you mouth along and hope? Do you go quiet and look supportive? Christian has a manoeuvre. Whether it's dignified is a separate matter. And would you ever leave a gig early, or is walking out an admission that you wasted your money?

Plus: Christian's past life on bass, a list that keeps growing, an audience-participation format that should never be made, and a warm welcome to the patrons, who were very quiet this week.