A day before Jackson broke the record, Sally Gunnell had done the same in the women's 400m hurdles. Gunnell was satisfied with her run, but what she and Jackson had in common, besides their records and their medals, was a technical emphasis that differs from many of their rivals'. While many of the opposition concentrate on their speed over the hurdles, Jackson and Gunnell concentrate on speed between them. Jackson could afford to get five hurdles wrong in Stuttgart because it was what happened in between that counted. His and Gunnell's mastery of this technique makes them favourites to take a couple more golds at Helsinki this week.
It was not ever thus in British hurdling. Athletes used to be carefully nurtured over the hurdles with their lead leg straight and their torsoes dipping so low that they almost head-butted their front knee. Beautiful jumping technique, but not successful in sustaining speed on landing: 10 starts in a short race does not a winner make.
But there has been a coaching revolution, much of which has been instigated by Bruce Longden, who looks after Gunnell. Longden won a scholarship in the late Seventies which enabled him to visit a number of European countries and study their methods. 'I found that their hurdling technique was not anywhere near as precise as ours,' he said. 'And so I went into it mechanically, with scientists.' Further research at Crewe and Alsager College confirmed much of what Longden had suspected: 'There was no doubt about it. The hurdlers had to get as near as possible to a normal running action. A lot of hurdlers, when they are crossing the hurdle, leave their bum behind. They throw a leg at the barrier and their centre of gravity is still behind it when they are looking to get their lead leg down.' This distribution of body weight, Longden found, reduces momentum. Making sure his hurdlers kept their abdomens forward became his priority, so much so that Gunnell adopted his coaching catchphrase, 'running tall', as the title of her autobiography. Longden also dispensed with the hurdlers' straight leg lead; a bent leg hits the ground quicker and is correctly positioned to pull away from the hurdle.
Gunnell knows that a perfect race will include 162 paces plus the 10 hurdles before she hits the finishing straight. Twice this year she tried 161 paces - one was dropped between hurdles six and seven - but this forced her to lead into the eighth with her weaker right leg and the angle of the bend caused her to clip the hurdle.
So is she merely a programmed athlete? With such precise parameters why couldn't other hurdlers achieve the same success? Longden and John Bailey, the national 400m hurdles coach, both attribute Gunnell's victories to her singular mastery of their principles allied to a necessary athletic ability. Her background in sprint hurdling, where even more emphasis is placed on technical precision, they say, is largely responsible.
Apart from technique and speed, Gunnell also has the ability to think her way round the 400m hurdles, one of the track disciplines that requires a lot more than physical power. If there is a headwind down the back straight, for instance, she has to make a split-second decision on what to do, whether she should change her stride pattern, and if so, when to change it, so that her fallible right leg does not lead into the wrong hurdles. 'You can't be obsessed by your pattern,' she said. 'You've got to be able to adjust.'
Myriad talents indeed, though there are those who have matched her times without having anywhere near the same ability. 'I've got people in my event who can't hurdle for the life of them; their strength and their speed is what gets them round. Look at Sandra Farmer-Patrick.' She came second in Stuttgart, just 0.05sec behind the world record-breaker.