In a practical reprise of 2012's BBC Show at Salford – which made up half of the tour to promote the “Elysium” album – Pet Shop Boys bring a unique(ish) show to the Royal Albert Hall for a one off Teenage Cancer Trust performance. And whilst I have loved this band for oooh, at least three quarters of my life, and the combination of Johnny Marr, and an Orchestra, is a magical promise tonight sees the Pet Shop Boys play probably their most indulgent (song wise), and underachieving (in terms of audience response), show I've ever seen.

It all comes down to the songs. The songs that brought us into their fandom weren't aimless ballads, or unsuccessful attempts at depth. The songs that brought us in touched us, spoke to us, meant something to us. Songs that discussed what and who we are, now and then. Songs that made us see and feel the world differently. And so few of those songs were played tonight. Not every song any band writes is brilliant ; even The Smiths and The Beatles fell foul of that.

Maybe I was expecting too much : certainly, there is a unique power behind seeing them perform so many rare songs with an orchestra. When it hits – when they play songs deserving of the scale – it's staggeringly effective. When it misses – when an orchestra is used to buff up deservedly unappreciated stinkers like “Hold On”, and “Breathing Space” - the effort falls depressingly flat of the target, and I'd've rather the show been shorter than waste the time on such insubstantial material. Especially when songs like The Theatre, Being Boring and Go West, sublime, perfect for the moment, built for an orchestra, are inexplicably ignored.

It's an evening with a handful of hits, and too many misses. An evening where It Couldn't Happen Here is played live for only the second time, and it is mindblowingly good.

There is a majesty when they tower through Jealousy with Chris Lowe there, playing parts on a grand piano that have, for so long, just been sequenced as he only has two hands. There's no doubt how much they both do in the studio that can't be replicated live on stage : the popular conception is that Neil stands around looking bored whilst Chris just does much the same and other people do all the work – and it is wrong.

But also, this is practically a carbon copy of two previous one-off orchestral shows, and there's little 'new' that hasn't been heard before at those two shows. Little indeed. Not one song is less than 5 years old, and nothing from the past two albums is represented at all. It's as if they just reloaded the “BBC Salford 2012” and “BBC Mermaid 2006” Hard Drives, shuffled a few songs around, and let loose. I guess I got to see the “Elysium Orchestral” tour, five years too late.

There's a lot of obscure material in here, most of it taken from 2012's underwhelming “Elysium” (in fact, earlier on we signaled out our two least favourite Pet Shop Boys as being 'Hold On' and 'Requiem In Denim And Leopardskin', only on the grounds I'd forgotten the existence of 'Breathing Space'). In fact, there's four songs taken from that album in the night, alongside the yet-unreleased 'He Dreamed Of Machines' from the Alan Turing song project* and For All of Us from the mostly forgotten “Closer To Heaven” musical – all rare and unusual choices, but they lose most of the audience, and it is difficult to get them back. .

*no one should ever call anything a project. Art isn't a business plan.

And many of these songs have been played once once or twice before : The Survivors, Later Tonight, Tonight Is Forever and It Couldn't Happen Here, are powerful, effective, under-appreciated and simply not played enough. Later Tonight gets its first performance since 1989. You cannot accuse the band of taking an easy route, choosing the obvious songs and playing some obvious choices I'm Not Scared, My October Symphony, Pandemonium, Being Boring and ... but I do wish they had.

Whilst the orchestra play their parts effectively, and it's glorious to see (but not always hear) Johnny Marr adding that perfect texture he contributed to the albums, it's an evening where I feel the crowd are seemingly pulling in a different direction ; where there's definitely two people sleeping on my row (one is, I think, snoring, which is impressive), and where by the tell tale glow of your phone, there's a lot of distraction.

That, combined with a very underwhelming sound mix where neither the electronics, nor the orchestra are loud enough – and where you can talk at normal conversational level and be louder than the act – and it's not going to be a great show by an absolute standard.

It's a downright perverse choice of material that emphasises the chinstroking, thoughtful side of the band, but also, when you've paid for a show – even if that is exactly what you got – there must be a kind of trade off between band and audience : an understanding of the social contract. There's an expectation of a sort around the promise and the delivery. Even we got what we paid for, some of us got everything we didn't want and less. I can't pretend I was enraptured for large parts of the show, I did try, but the pacing and structure of the show was uneven, veering between lively, dramatic material deserving of the scale of an orchestra, and mid-paced, second division ballads hoping for depth but falling short – you can't add meaning to something with an orchestra, only emphasise what it already there. Whilst it was undoubtedly unique, and an experience, the night was underwhelming in some respects – which is a great shame, as there was so much potential, and many different songs crying out for the occasion, that this wasn't quite made real.

Left To My Own Devices
Tonight Is Forever
This Must Be The Place
Rent
Later Tonight
New York City Boy
Miracles
The Survivors
Leaving
Jealousy

- Hold On
It Couldn't Happen Here
For All Of Us
Can You Forgive Her?
Breathing Space
He Dreamed Of Machines
Requiem In Denim and Leopardskin
Indefinite Leave To Remain
West End Girls
It's Alright
It's A Sin