You'll be aware that Justin Bieber took the stage at London's O2 this week two hours late. It reminded me of a gig in Glasgow a few years ago when Hull's uber-jangly, Marxist undergraduates The Housemartins played the Barrowland ballroom.
Given that the venue's own advertising described it as "inordinately sweaty, occasionally terrifying", it's not the kind of place you'd want to keep the audience waiting for two minutes, but The Housemartins foolishly stretched that to two hours. So there we all stood, foot-sore and lager buzz dissipating. Suddenly, on to the empty stage walked two men in thick glasses.
There was utter silence as the crowd processed the fact that this pair of nerdy-looking spods were not The Housemartins. Of course, what the crowd didn't know - and what the country wouldn't know for a year or two - was that this was The Proclaimers. The then-unknown duo started singing what sounded like folk songs in very thick Edinburgh accents (never popular in Glasgow), and the crowd immediately registered its opinion.
Back in the punk-hungover 1980s, this meant a revolting (if unambiguous) torrent of spit. Probably glad of their glasses, the twins battled on and, incredibly, within six songs, had turned the shower of flob into applause and, by the end of their set, into a standing ovation. I have never seen such a turnaround.
And while I'm not suggesting Justin employs The Proclaimers in case he runs late, it would be a way of ensuring that his fans have run out of spit by the time he hits the stage.