Monaco, 1971: the opening scene of Roman Polanski’s fly-on-the-wall documentary Weekend of a Champion shows perpetual Formula 1 winner Jackie Stewart and his achingly beautiful wife, Helen, leaving the Hotel de Paris and heading into Monte Carlo.

The elfin Stewart, just shy of 32, is an instantly recognisable brand: long hair, black corduroy cap, white overalls, sideburns down to his jawbone, impish smile usually beneath blowfly sunglasses. Helen, then 30, sports a cap too, and the couple chats about the weather.

They stroll down the pit lane, and Stewart wins yet another Grand Prix in his specially built Tyrrell 003, despite a broken balance bar depriving him of back brakes. No single chassis has won more formula one grands prix, driven each time by one man: wee Jackie, the clay pigeon shooter and mechanic from his family’s garage at Dumbrook, near Glasgow, who was once just written off as plain dumb.

John Young Stewart would rub shoulders with Princess Grace, pal up with Princess Anne, break bread with Andy Warhol, beat a ticked-off Bing Crosby at charity golf, and strike a lasting mateship with actor and fellow Scot Sean Connery in that intoxicating era of James Bond, bikinis, champagne and fast cars.

It was Connery who impressed through example how Stewart should modestly wear the fame of three world championships and 27 Grand Prix victories. But unlike cool Bond 007, the suave wit of driver 003 was leavened with a recurring fury.

Stewart, now 68, recently found himself watching Weekend of a Champion again, and behind the witty young driver in Polanski’s film he saw a second Jackie Stewart, “a more intense, fractious character, quick to judge, quick to snap”.

During his career, Stewart drove smoothly and meticulously; but in public and private he could be quickly irritated, volubly critical. As a child, he had had learning difficulties and had struggled to make himself understood. As an adult competing in Formula 1 for eleven years, he endured the sport’s slaughter of no fewer than 57 friends and colleagues on the racetrack. Many deaths, Stewart firmly believed, had been preventable.

The most poignant was that of Stewart’s 29-year-old teammate, the flamboyant Frenchman Francois Cevert, who liked to wear a double-breasted, ankle-length fur coat off the track, and whom Stewart came to think of as a brother. Cevert was killed on October 6, 1973, during practice at the US Grand Prix at Watkins Glen – the event where Stewart had for months secretly planned to, and promptly did, retire.

Stewart himself looked into the wreckage, his “younger brother” still strapped in. For 34 years now, Stewart notes in his newly released autobiography Winning Is Not Enough, he has regretted walking away from the wreckage after two minutes, presuming Cevert dead: “Maybe I could have waited there and talked to him … when he breathed his last breath,” Stewart writes. “I don’t know.”

Stewart had become a pariah among same racing officials and even some fans and journalists for leading the charge of drivers demanding barriers be installed at tracks, that flame-retardant driving outfits be made mandatory, and thorough safety checks be carried out before racing. His critics argued drivers knew the risks when signing up.

Yet Jackie Stewart made F1 driving a much safer sport, with no deaths of drivers since Roland Ratzenberger and Ayrton Senna were killed at the 1994 San Marino Grand Prix.

During his book promotion, Stewart will be a keen spectator at the Australian Grand Prix in Melbourne between March 13 and 16. “I think Albert Park’s a very good, safe racetrack indeed,” Stewart says. “Good debris fencing, good deformable structures on the walls, good runoff areas in most places. It’s a top line circuit.”

That is no small endorsement for the Melbourne event. Australian-born former Ford boss Jac Nasser has described Stewart as the “critic from hell”. The late Ford public relations head Walter Hayes, who signed Stewart to the company in 1964, once said: “He can be hugely irritating as you know, and he sometimes has opinions of his own that take a little chipping away at.”

Since selling his Team Stewart business interests to Ford in 1999, Stewart has had time to reflect and walk his Norfolk terriers Pimms and Whiskey around Switzerland’s Lake Geneva, where he and Helen – who long ago used her nail polish to affix half a yard of Royal Stewart tartan silk to his white helmet – still live after 45 years of a stoic marriage.

Why is she such a stayer? “Most women are somewhat emotionally stronger than men in many ways,” Stewart says. “If we’d been the same sort of people, it would have been more difficult; in a marriage where both people are determined to have their own way, something’s got to give. Helen did an amazing job of keeping our sanity when so many friends were dying.”

In his day, as if to add to the cruelty, drivers such as Stewart were expected to simply race on after each crash – to drive through the smoke and flames, occasionally glimpsing bodies of mates on the track.

These days, Stewart admits to “floods of tears” over lives lost. Back then, he hardly ever cried. “A psychologist probably would have had a field day with me,” he writes.

He was never offered counselling? “I never had any of that. It was something you learned to deal with; I [imagined] I owned a little pouch containing a potion which during these high-adrenaline periods would dilute the grief and allow me to still function.”

For many years, people assumed Jackie Stewart was stupid. He remembers being nine years old, trying to read in front of his class, seeing only a “jungle of letters” and feeling ashamed. Finally, in 1980, at age 41, when the youngest of his two sons, Mark, was diagnosed with dyslexia, Stewart was diagnosed with the condition too.

Even today, Stewart cannot recite the alphabet beyond the letter ”p”: he dictated his autobiography onto a recorder, had a secretary type it up and an editor finesse the prose.

Yet some dyslexics have a photographic memory, he notes: throughout his career, Stewart would look at a racing circuit and “bank its features in my mind”.

“When you’ve got dyslexia and you find something you’re good at, you put more into it than anyone else; you can’t think the way of the clever folk, so you’re always thinking out of the box,” he says. “So you sometimes can be considerably better at what you latch onto than anybody else. It saved my life, because I had been humiliated and frustrated.”

There are poignant family notes sounded in the book. Stewart’s mother, Jeannie, who died in 1977, never once mentioned or acknowledged her youngest son’s racing career because he had defied her wishes when he entered the sport in the first place – and lied to her for several months by hiding his budding career from her. Stewart’s father, Robert, had to visit neighbours’ houses to watch TV to see his son compete.

Has Stewart forgiven his mother her lack of acknowledgement? “Oh yes. I knew deep down she was fully aware of what I was doing. It wasn’t as if there was any antagonism. My mother was a very determined and stubborn person – a very Scottish person.”

* Winning is not Enough is published by Headline, $35.