Garbage, Electric Ballroom, London <br></br>Cathal Coughlan, Borderline, London

Shirley's gone a bit Lara. Slicked back hair, white vest, combat shorts, key chain, big boots – Ms Manson looks like she's come to kick ass rather than rock the house.

Either that, or she's here to sell us some Lucozade. Garbage, after all, are masters and mistresses of the corporate tie-in. Tonight, they open with "Supervixen", the one from the snowboarding on Channel 5, and follow it with "Temptation Waits", the one from Buffy The Vampire Slayer. Lest we forget, Garbage are the band who were assembled by Nirvana producer Butch Vig and a couple of his session musician mates, and Shirley, then already in her second band Angelfish (she'd started out in Goodbye Mr Mackenzie), was recruited from MTV because she looked good on video. This, of course, cannot be denied: with her foetal headshape (reminiscent of that scary alien girl from the Nintendo ads) and her ginger albino Celt-flesh, Manson oughtn't to be pop star material, but she's undeniably video/photogenic.

Garbage are artisan-musos, been there, done that, hand-picked to do a job: Butch Vig's ill tonight, so he's replaced "himself" with a session man. None of which would matter if Garbage weren't at such pains to seen to be "real" (whatever that, in a pop context, actually means). Just as "Cake", in the autocued words of Bernard Manning on Brass Eye, is "a made-up drug", so Garbage are a made-up band. I have no problem with this in principle – some of my favourite pop groups were completely fabricated – but Shirley doth protest too much.

Telling us that she was obliged to mime on Top of the Pops earlier in the day, she's funny at first ("I proudly faked it, and I do it very well, and this time I did it for the entire United Kingdom"), but then ruins it by mocking a pop act she met on set, who were "proud to be manufactured". And how do you feel about being manufactured, Shirl? Embarrassed? Ashamed?

It's a hits set – the dreary "Milk", the smug "Stupid Girl" (audience thinks: "Yeah, she's so right! I really hate stupid girls too! Isn't it great that I'm not stupid?") and "Only Happy When It Rains" (why didn't The Mary Chain sue?) – and they do have their flashes of quality, notably "Special", their finest moment (not least for the Star Wars-esque video).

But flashes are all they are. On record, on its own terms, Garbage's stylised, airbrushed alterna-pop can work. In concert, their desperate trumpeting of their own spurious authenticity ruins everything. This, ultimately, is their downfall: Shirley labours to create the perception of a no-bullshit kinda gal – a hybrid of Tank Girl and Siouxsie Sioux – but the very same mental mechanisms which filter out bullshit also filter out The Good Stuff. And this is why Garbage will never be anything more than what they are: the Indie Texas.

It's always the quiet ones you've got to watch. In the 1980s, Cork-born Cathal Coughlan was one half of Microdisney, the band he formed with Sean O'Hagan (now a High Llama). Perennial residents on the Janice Long playlist but permanent strangers to the charts, Microdisney made a melodic, mature, slick, slightly Steely Dan-ish sound which, in a world where The Smiths existed, didn't do enough to warrant investigation.

What came next, though, was a lot more interesting. Coughlan formed the Fatima Mansions, dispensed with any dreams of mainstream acceptance, and began a full-time career as agent provocateur/enemy within. In no particular order, Coughlan commemorated the fall of the Iron Curtain with an extraordinary six-minute single called "Blues For Ceausescu" ("Go to England, baby-raper, false economist, call yourself King Charles III / Nobody will notice, nobody will be around / There is no constitution"), paraphrased Thatcher on "Only Losers Take The Bus", had a hit of sorts with a terrifyingly anti-musical version of Bryan Adams's "Everything I Do (I Do it for You)" on the B-side of Manic Street Preachers' "Theme From M*A*S*H", performed similar horrors on REM's "Shiny Happy People" (years before V/Vm had a similar idea), collaborated with Sean Hughes on a maliciously satirical side project called Bubonique and, supporting U2 in Milan, sparked a religious riot.

In 2002 Coughlan, now solo, is on the cusp of his forties. Age has not mellowed him. With his speed-freak eyeballs, glistening upper lip and Action-Man-gone-Awol haircut, he takes to the stage of the Borderline looking like nothing so much as a photofit of a wanted terrorist. Tonight's first song depicts Ireland as a land of "cultural tourists and TB graves" where "every shed is a church". Introducing another song, he says that he would call it a morality tale, "but I have no morals to impart." You're getting the idea: The High Llamas this ain't.

A career-trawling set takes in Microdisney's song about Boy George's heroin bust, "Singer's Hampstead Home" ("He had bad lines to say / But he said them in a really stylish way"), The Fatima Mansions' "Loyaliser", and his own "Drunken Hangman", detailing – I'm not making this up – an imagined liaison between a London-Irish hitman and a runaway Romanov royal in the 1950s.

His backing band, the Grand Necropolitan Quartet, work up a Bad Seeds-like storm of cello, drums and guitar, while Coughlan does things to an electric kepyboard which surely violate the warranty. For the most unnerving part of Coughlan's performance, however, he is completely silent. As a song meanders through a lengthy five minute instrumental coda, Cathal sits immobile, staring into space.

He doesn't blink once.

s.price@independent.co.uk