The Pogues, Academy, Leeds

Somehow Shane MacGowan stays upright long enough to lead a stout-soaked Christmas knees-up

When the dust settles after the Third World War, the population of Earth will read as follows: Keith Richards, cockroaches, Shane MacGowan.

Twenty-five years of bad living and somehow MacGowan's still standing. Not that he isn't showing the scars. When "Dirty Old Town" was recorded, MacGowan was a young man pretending to sound like an old derelict. Nowadays he doesn't have to pretend. It was Sir George Young, the Conservative MP, who infamously described the homeless as "the people you step over on the way to the opera", and it's a phrase that leaps to mind when contemplating the figure of Shane MacGowan, shuffling on stage in a long, battered overcoat, a drink in his hand, and now so dentally deficient that his diction makes it hard to decipher which song he's singing. But there's a twist, in his case: he is the opera.

There's a certain ghoulish element to a Pogues gig: during the slow songs, people wave not lighters, nor mobile phones, but brimming pint glasses in a bittersweet salute. This is the aspect of The Pogues that has always put me off: the communal attempt to reverse human evolution. But it was never the whole story. In the mid-1980s, The Pogues dared to be romantic at a time when that just wasn't cool. It was this that saved them from a fate as a mere footnote to London's barely remembered cowpunk scene.

Take, for example, "The Sick Bed of Cuchulainn", a posthumous tribute to a force-of-nature Irishman who once "decked some blackshirt who was cursing all the Yids". Then again, the beeriness can't be written out completely. "Sally MacLennane", given a barnstorming rendition here, may appear to be a raucous homecoming hymn about rejoining the girl you love, but it's actually about a type of stout ale.

The other Pogues – all nine of them (including a horn section with the splendid nickname Cup O' Tea & the PGs) – are as affecting as any Irish folk ensemble you care to mention, with their armoury of mandolins, accordions, penny whistles, banjos. It's they, as much as MacGowan, who make songs such as "A Pair of Brown Eyes", "Rainy Night in Soho" and the aforementioned "Dirty Old Town" so moving, causing you to sway along despite yourself.

They're at their best, though, when they shift through the gears, on any number of those Pogues songs that start deceptively slowly until someone shouts "three, four!" and they're away, hurtling chaotically. The most obvious example is the finale "Fiesta", in which Shane and sidekick Spider Stacey provide percussion by bashing themselves over the head with a tin tray.

It's Ella Finer, daughter of banjoist Jem, who sings the female part on the song everyone's been waiting for, "Fairytale of New York". The sweary "You scumbag, you maggot, you cheap lousy faggot/Happy Christmas your arse, I pray God it's our last" may have been one that caught the censor's ear, but the killer couplet is "I could have been someone .../ Well, so could anyone!". It's the reason why The Pogues' December tour is now a fixture on the Christmas calendar. If they don't bash themselves too hard with that tray, it ought to continue for a few decades yet.