Jim Clark was almost certainly the only Formula One world champion as comfortable with a shepherd’s crook as with a steering wheel. Had he not been killed in Germany 50 years ago this coming weekend, his family’s farm in the Scottish borders is the place to which he would have returned when his days on the globe’s racetracks were done.

His death stunned the world as profoundly as that of Ayrton Senna a quarter of a century later, and for much the same reason. The two champions shared a virtuosity that lifted them to a level above their rivals and made them seem invulnerable.

Both accidents also left behind them a sense of mystery. When Clark died on a forested section of the Hockenheim circuit during a Formula Two race on 7 April 1968, leaving the track on a fast curve at 160mph, there were no spectators or TV cameras in attendance. The only witness was a German track official who reported seeing the driver’s efforts to take control of the car before it left the track and plunged straight into the trees, where it was torn apart. Clark, his neck broken by the impact, died instantly.

The immediate assumption was that something had broken on the car. It was a Lotus, the team with which Clark had secured both his F1 world titles and become the first British winner of the Indy 500. Lotuses were fast but sometimes fragile. Nowadays the best guess is that a slow puncture led to the tyre rolling off the rim when the car turned into the curve.

As the news spread fast around the world, the reaction was one of universal shock and distress. “Motor racing almost died of a broken heart,” wrote Eric Dymock, Clark’s biographer and this newspaper’s grand prix correspondent at the time. One of Clark’s closest rivals, the American driver Dan Gurney, said: “It destroyed me. I was drowned in tears.”

Gurney died this year, aged 86, a one-time Californian hot-rodder still tinkering in his garage to the last. Clark was taken a month after his 32nd birthday, denied not just further championships but an eventual resumption of the simpler life from which he had emerged.

He was 23 and still a farmer when I glimpsed him for the first time on Easter Monday in 1959 at the little Mallory Park circuit in Leicestershire. He won four races that day – three in a brawny Lister-Jaguar, one in a little Lotus Elite – which was more than enough to impress a schoolboy spectator who, although barely out of short trousers, could sense that a special gift was required to tame two such contrasting cars with equal success.

He was an easy hero to adopt. If Stirling Moss, another virtuoso, had been a creature of the 1950s, Clark – despite his relatively conservative look and modest, unpretentious demeanour – was a better representative of the new Britain being defined by the Beatles, Mary Quant and the Bond movies.

In 1965, during the summer of Help! and Like a Rolling Stone, he won the British Grand Prix at Silverstone with one of his most remarkable drives. His Lotus had established a 30-second lead over Graham Hill’s BRM with about a quarter of the race still to go when its engine started to lose oil pressure. To postpone the inevitable blow-up, he started switching the engine off in the corners and coasting through before firing it up again on the straights.

If you happened to be spectating from the bank at the end of the pits straight, it was strange to hear the Lotus come through in virtual silence, with an eerie whistle rather than a full eight-cylinder roar. Hill was catching him at a rapid rate but Clark’s superlative judgment enabled him to take the chequered flag still three seconds ahead of his pursuer.

When he died he had won 25 grands prix from 73 starts, a success rate putting him behind only Juan Manuel Fangio (24 wins from 52) and Alberto Ascari (13 from 33) and ahead of Lewis Hamilton, Michael Schumacher, Jackie Stewart, Senna and Alain Prost. There were fewer races per season in those days, of course, but the competition against the likes of Stewart, Gurney, Jack Brabham and John Surtees was just as strong.

Clark was held in affection as well as admiration by his rivals, who were amused by his indecisiveness out of the cockpit. His friend Sir John Whitmore, with whom he shared a drive at Le Mans in 1959 and whose Mayfair pad became his London base, remembered the contrast between the innate finesse at the wheel and the social dithering.

“I’d say, ‘Let’s go out to eat – which restaurant would you like to go to?’ He’d say, ‘It’s up to you.’ I’d say, ‘Shall we go to a movie?’ He’d say, ‘Yes, but you choose.’ He had a very lovely girlfriend, Sally Stokes, for a long time, and everyone said, ‘Why aren’t you marrying her?’ They were very good together and she wanted to get married. But he couldn’t do it. He never made any decisions. Until he got in a racing car.”

His gravestone in a village churchyard a couple of miles from the family home describes him, before any mention of his racing activities, as a “farmer of Chirnside and of Pembroke, Bermuda”.

The second address was added by his executors in order to ward off the Inland Revenue, whose initial claim to 91p of every pound he earned had led to him to take refuge first in Paris and then in Bermuda. The taxmen never believed him and pursued his estate for several years after his death. They couldn’t catch Jim Clark, either.