Kid A finally arrived in September 2000. An artfully sequenced collage of drones and tones, fissures and moans, Radiohead’s audacious reinvention proved impenetrably self-indulgent to some, heroically avant-garde to others. The cultural significance of a huge global rock act releasing these fragmented, opaque, largely guitar-free moonscapes on a major label was almost palpable.

This was head music for post-rave ears, the weightless abstraction of techno wedded to the weighty inner monologues of rock. Comparisons with late-’60s Beatles and early ’70s Pink Floyd proved irresistible. Miles Davis, PiL, Joy Division, My Bloody Valentine and Aphex Twin were added for good measure.

With no singles, no videos, minimal press and only a handful of hysterical (but useless) “i-blip” TV clips as promotion, Kid A carved its own rarefied media space. Perhaps because it was the first Radiohead record to abandon the visceral thrust of what Thom once called “all the ugly male sleazy semen-smelling rock bullshit”, some called the record a failure of nerve. Were Radiohead raising the stakes or simply retreating to the experimental margins?

“The dangerous thing is that all this is pre-supposing we were somehow trying to be experimental,” frowns Jonny, “which I’m not sure is true. To me, half of Kid A sounds like half of OK Computer. There was no line drawn underneath, we just carry on. I mean, for the market we’ve arguably been making wrong turns since The Bends, and that was so long ago. But it’s not something we try and do or avoid, really. I think if we’d done three or four albums full of “Creeps” or something, and then done this, I could understand. But we’re just drifting off and always have been.”

An emphatic validation came when Kid A topped the album charts on both sides of the Atlantic. But even this achievement Colin Greenwood dismisses as a fluke. “It was like prize-giving day at the media,” he grimaces. “They had the gold trophy that the headmaster was about to give to us because of previous form. Then they heard the record and it got put back in the glass cabinet for the next people. It was like we won before we’d actually done the race.”