By Chris Charles BBC News Online

If only - the most wistful couplet in the English language.

If only Elvis had stuck to vitamin pills. If only James Dean had caught the bus. If only Kurt Cobain had bought a water pistol.

Alas, fate decreed otherwise and we are left instead with a legacy which will serve as a blueprint for aspiring guitar bands in decades to come.

Rather than bringing down the final curtain on the Nirvana story, this greatest hits collection is more of an unfinished symphony - a poignant reminder of what might have been.

The only new song here is You Know You're Right - a track recorded just three months before Cobain's untimely death in 1994.

It's vintage Nirvana, flitting between soothing warble and rampant snarl - and even though you know it's eight years old, you have to convince yourself it wasn't finished yesterday.

You Know You're Right has finally been allowed into the public domain following lengthy legal wrangles involving Cobain's widow, Courtney Love.

His wife Courtney Love was involved in legal wrangles over the band

Predictably, the record company have decided to cash in by using it as the carrot to flog Nirvana's back catalogue to the fans who should already own it. Ice and Eskimos anyone?

The remaining 13 tracks span four albums, including Sliver and Been A Son from Incesticide and Heart-Shaped Box, Rape Me and All Apologies from In Utero.

Nevermind also features heavily, with the likes of Lithium, In Bloom and Come As You Are standing alongside the inevitable Smells Like Teen Spirit.

As compilations go, it's a reasonable effort, but the inclusion of only one song from debut album Bleach confirms it is aimed more at the mainstream market.

Not that there's any argument about the choice of track to close the album - Cobain's goosebump-inducing rendition of David Bowie's The Man Who Sold The World.

Who back in1973 could have foreseen The Thin White Duke being upstaged by a scruffy young man wearing his grandad's green cardigan?

Cobain was the man who told the world - repeatedly - of his inner anguish. And while millions listened, ultimately no one was able to save him from himself.

If only he'd realised how important he was.