This was something of a homecoming for Declan. Although Elvis was born in Liverpool, I suppose you could call him a genetic paddy, a fact which maybe influenced his decision to play Dublin and Belfast as the first dates on his tour.
His chromosome compatriots were hugely glad to see him. The Belfast kids, obviously, don't have bands queuing up to play their city, and the ones that do turn up are as often as about as exciting as a John Miles interview.
So the reception for Elvis was immense. The crowd made a racket worthy of a cup final crowd. No trouble either apart from a few dumb Nazi salutes (because of "calling Mr Oswald with the swastika tattoo").
What violence there was happened onstage. The vitriol came from the speaker stacks. Elvis may not be angry, but at least he seems irritated. That edge to his voice is agonising.
But it's a different man who peers out from under the shadow of the vast organ pipes that fill the rear of the packed hall. A not-so-clinical artist, a less vicious vision.
Costello no longer has a sneer of contempt. He is utilitarian instead of arrogant; introduces songs and sings them. No more posturing, but maybe that's because he isn't playing to the Londoners he holds so much antipathy for.
And the performance is somehow more 'live'. Not so long ago, Costello was approaching gigs in such a scientific fashion that the songs were as close to replicas of the studio as they could be; each solo measured, each intonation considered.
In Belfast the approach was rougher, and looser, a sacrifice of precision for spontaniety. It's a better approach. The huge excitement Costello drummed up — four encores ended the show — cannot be put down purely to the music starvation of the punters. There was a spark there that was absent before. Considering the perfection of his previous tours, I find it hard to swallow that he's actually improved, but he somehow has.
I was jammed in the crowd and stuck in the wash of excitement, more enthralled than I have been since the last time I saw him perform.
Last year I described Elvis as a genius. He holds me in contempt for that, apparently, as he holds nearly everyone in contempt for something. It seems I was being premature.
But I wasn't, of that I'm completely sure. Elvis has genius and is a genius. It's the first time I've used that word to describe a new artist for ages, and I mean it. He is the next big thing, and the big thing after that, and after that. Costello will endure because he can't be ignored.