"That's all I got," croaks Keith Richards, stumbling to an abrupt conclusion on his new song Crosseyed Heart. But clearly, that is not all. For here he is with an album of the same name: another warm, swampy, deeply groovy concoction of rock, blues, country and soul, full of romantic tenderness and hard-earned wisdom, delivered in a spirit of pure vintage class.An accompanying documentary, Under the Influence (exclusively on Netflix), features Richards dispensing one-liners and whimsical anecdotes with a gruff whisper and chuckle, revealing nothing much except that he's a happy old rocker. And when he runs out of things to say, he just lets his guitar do the talking.Watching the old buccaneer in action, you have to wonder how he became so universally loved. He has been hailed as the Human Riff and anointed the world's most elegantly wasted human being, the bad-boy pin-up for junkie chic with the heavily wrinkled face. Surely Richards should be nobody's idea of a role model: self-indulgent, irresponsible, a star squandering his gifts on drugs and alcohol?Back when it all began, it was Mick Jagger who was the epitome of sexy, rebellious cool. Richards was his scruffy sideman with a swaggering line in guitar riffs. Aficionados loved him but the dreamy Brian Jones was hailed as the band's genius (not least by Jones himself). As the 1960s ended, though, there was a shift in the Stones hierarchy. Richards was getting his look together: cigarette permanently attached to lower lip, jagged hair cascading around his head like an electrified mop, ragged gypsy clothing accessorised by skulls, rings and bandanas.Dark-eyed and lean, Richards, even with his piratical flamboyance, took on a very masculine presence next to Jagger's camp theatricality. It corresponded with his growing maturity as a musician. Richards took the reins for the Stones' greatest run of work, from Beggars Banquet in 1968 to Goats Head Soup in 1973, reshaping blues for the modern age. But at the same time he was developing habits that have made him the personification of all the most extravagant myths of sex, drugs and rock 'n' roll."My life's been dedicated to avoiding trouble," Richards once told me, "so it's pretty funny how much I've run into."He seemed to have a curiously charmed existence, emerging unscathed from car wrecks, house fires and run-ins with the law.While Richards spent much of the 1970s in a stoned stupor, Jagger kept the Stones rolling, saving them from financial ruin and turning them into a lucrative entertainment brand. By the 1980s, Richards had pulled back from hard drugs but was a borderline alcoholic whose musical powers were much diminished.Attempts to resume creative leadership of the band led to a power struggle with Jagger that Richards refers to as "World War 3" and has still not been satisfactorily resolved. The Glimmer Twins (as they once styled themselves) have been on barely civil terms for decades, with Jagger particularly wounded by injudicious comments in Richards's best-selling 2010 autobiography, Life. It took the intervention of others to get the Stones together for their 50th- anniversary shows in 2013, and it has taken almost three years of touring for them to reach a point where, according to Richards, they might record a new album."Don't know where, don't know when yet - but it's definitely in the works."In a strange way, Jagger has come to be regarded as something of an uptight dilettante because his healthy lifestyle, sense of organisation and discretion don't chime with the band's original rebellious spirit.It is Richards's irreverent swagger that the baby-boomer generation waxes nostalgic for, even if few would adopt his lifestyle. He's like a favourite naughty uncle; celebrated as an unlikely survivor.It helps that, rather than being damaged by hard living, Richards seems to have been enlarged by it. He has an affable, gregarious nature. Possessed in photos of a death's-head cool, in person he is smaller, looser, paunchier and softer than you might expect.His exaggerated gestures, drawling speech, laid-back demeanour and rambling anecdotal style are all signs of a system that never runs on empty.When he says he has given up "the hard stuff", I think he means there's a bit more mixer than alcohol in his drinks these days.I'll never forget the time I spent with him in Los Angeles in the 1990s, when he practically kidnapped me for two days of talking and drinking. His favourite tipple was vodka and fizzy orange, a foul concoction. There were frequent visits to the bathroom, from which he would return curiously refreshed.He is possibly the least showy guitar hero ever to strap on an axe. You rarely hear him take a screaming solo. What he likes is something more indefinable, non-standard tunings, unusual chord shapes and droning electric mantras, squeezing every nuance and variation out of a two-chord trick. He calls it "the feel" and says "it's got to have guts and that almost superhuman capability of projecting itself".Richards lights up when he talks about music. "The rock 'n' roll is important. The sex and drugs is just something that happened to me along the way," he says.The album Crosseyed Heart is out now. The documentary Keith Richards: Under The Influence is available on Netflix...