Both the Benetton and the Williams teams use Elf petrol as part of their deal with Renault, whose V10 engine has been the most powerful in Formula One for the past four years, taking Nigel Mansell and Alain Prost to successive championships, and almost earning the title for Damon Hill last season after the death of Ayrton Senna. And it was Elf whose product broke one of Formula One's typically arcane rules.
Petrol alone is unlikely to be the reason for Renault's enduring supremacy in the face of major efforts from the likes of Fiat (backing Ferrari), Ford, Yamaha and Mercedes-Benz. But it might make a difference of a couple of dozen horsepower, which can be crucial in a sport where great scientific intellects, vast research facilities and huge manufacturing budgets tend to reach more or less the same conclusions, meaning that the best teams are rarely more than a few tenths of a second apart in performance. Schumacher's advantage over Berger in straight-line speed was a particularly explicit example of a big gap between teams expected to be more or less on a par.
While it is not one of the more compelling aspects of a glamorous sport, petrol has been a controversial subject in grand prix racing for more than a decade. In 1983, the Brabham-BMW team won the title by achieving a yield of more than a thousand horsepower from a 1.5-litre turbo-charged engine through the use of a secret mixture colloquially known in the pit lane as "rocket fuel". Since then even more exotic compounds have been used in the attempts to produce more efficient combustion and therefore greater power. The relatively unexceptionable smell of pump petrol was replaced by a more toxic aroma as the major suppliers - among them Shell and Agip, the Italian national petrol company - strove to devise new chemical cocktails in partnership with the engine manufacturers. So volatile and potentially harmful were the new compounds that exhaust gases had to be piped out of the pit garages when the cars were being warmed up, in order to protect the mechanics.
In recent seasons, as part of a drive to reduce the costs of racing, and also in an attempt to pay lip service to ecological concerns, the regulations have insisted on a return to regular pump petrol. But even within those narrow parameters, small variations can mean significant power gains.
The new verification procedure requires the teams to submit a sample of the fuel they intend to use throughout the 16-race series. The FIA's chemists, under the direction of the technical delegate, Charlie Whiting, then produce from each batch something they call a "fingerprint": a sample against which they can compare petrol taken at random from competitors during each meeting.
On Friday and Saturday at So Paulo, samples taken from Schumacher's Benetton and Coulthard's Williams failed to match the fingerprint. This did not mean that they fell outside the parameters of the fuel regulations - the mobile testing equipment taken to the races is not sophisticated enough to determine that - but it did mean that they were somehow different in kind, and that in itself is against the rules. The stewards instantly levied a fine of $30,000 (£19,000) on each team, and declared that any result obtained by either car would be provisional, pending further tests.
So when Schumacher and Coulthard took the grid on Sunday afternoon, were they aware that their efforts might be useless? If they finished in the top three, their cars would automatically be subjected to a thorough inspection. Were their petrol found to be the same as that used in practice, it would be a repetition of the first offence. Were it found to conform to the original pre-season sample, that might suggest that Elf had been either spiking their fuel with some performance-enhancing additive, or had brought a secret second batch of more effective carburant.
Now, too, all the samples, both from practice and the race, will be flown to a laboratory in England, where they will be analysed in depth. It is only during this process that the question of the basic legality of the fuel can be determined.
On the other hand, it may be that the FIA's on-track testing equipment is at fault. And accidents certainly can happen, even in this hermetically sealed world. When the post-race petrol analysis was well under way on Sunday night, a brief power cut destroyed all the data so far accumulated by Whiting and his men, forcing them to begin again. Since Benetton and Williams are to appeal against the verdict, and since tens of millions of pounds in sponsorship and the reputations of multinational companies are at stake, it would be surprising if Elf's lawyers were not preparing to enmesh Formula One in a courtroom battle over mishandled samples, inaccurate analysis, and perhaps political pressure.
After the deaths of Senna and Ratzenberger, the controversies over the accusations of cheating levelled at Schumacher's Benetton last year, and countless further rows over impossibly complex, ever-changing and always ambiguously worded regulations, it would be deeply ironic if the world's most technologically sophisticated sport, in which the full funding for a top-line team probably amounts to upwards of £70m a year, were to find itself sharing exactly the problems that so beset the organisers of humble foot races.Reuse content