"There was a time when we occasionally had a hit record," Charlie Reid good-naturedly chuckles midway through proceedings. To his right, brother Craig nods in sage agreement. Then they strike up the aching travelogue of Letter from America, and a happy sigh sweeps over the crowd, nestled in nostalgia.

There's something almost gleefully twee about the Proclaimers taken against the landscape of modern pop music.

Formed four decades ago as an acoustically-driven duo, their passage from proudly Caledonian troubadours with an agit-folk streak to surprise terrace anthem favourites and back again has bucked virtually all contemporary trends across the intervening years, and yet they remain preserved in amber; both timeless and out of time, an ageless relic as at home in the past as they are in the present.

This year marks their fortieth anniversary, and yet the language of their iconography remains the same as it always has. Close-cropped barnets, chunky-rimmed glasses, throaty Fife brogues interlocked in curiously honeyed harmony; taken in the soft-focus velvet surroundings of Leeds's Grand Theatre and Opera House, it could just as easily be 1993 as it is 2023.

They ostensibly arrive still in support of last year's Dentures Out, from which they draw a smattering of songs – but over a tight ninety-minute set, this is an affair primarily powered by the fan-favourite hits.

Backed up by a four-piece band as adroit with the lovelorn delicacy of Let's Get Married as the lively bounce of Sky Takes the Soul – one of several tunes from the pair long since entrenched into national cultural consciousness – it is an often-propulsive performance, with little in the way of soapbox theatrics so prevalent amid the current arena rock slate.

The rapid-fire rush through nearly two-dozen tracks can feel particularly breathless at points; even so, it is an approach that seldom shortchanges their best ditties, with the ribald burst of Over and Done With and the anti-honours riposte of In Recognition both particular standouts.

A closing straight in the final half-hour unlocks the big guns; Sunshine on Leith, I'm on My Way, I'm Gonna Be (500 Miles), all conjuring singalongs of varying beery tones. There's little pause for the frivolity of an extended encore break either, with a hoedown-flavoured romp through The Joyful Kilmarnock Blues to close before the crowd spill out onto New Briggate. It may be an early night, but few will feel shortchanged by Scotland's bespectacled bards.

Gig review: The Proclaimers at Leeds Grand Theatre and Opera House