Newly-crowned Formula 1 World Champion Lewis Hamilton is 'phenomenally good at driving', even when the car in question is 'an old snot-box' - that is the expert opinion of Top Gear's enigmatic Stig.

The McLaren-Mercedes star appeared on the BBC motoring entertainment programme last year, but the lap he recorded around the series' special test track for the popular 'Star in a Reasonably-Priced Car' feature remains unbeaten in the wet and - time-adjusted for dry conditions - is the quickest ever registered, ahead of fellow F1 title-winners Damon Hill and Nigel Mansell, and current grand prix rivals Jenson Button and Mark Webber.

Indeed, so good was the Stevenage-born ace's effort behind the wheel of the modest Suzuki Liana family saloon that he was only three tenths of a second adrift of the Stig's best marker - again on a dry surface. Top Gear presenter James May was clearly impressed.

"Lewis Hamilton is the fastest person ever around our track," he told Simon Mayo on BBC Radio 5 Live. "We used to have a separate board for Formula 1 drivers and former Formula 1 drivers because otherwise it wasn't fair, but we haven't done one recently.

"He was brilliant though, which is quite re-assuring, because there's always a little bit of you that thinks 'well is it really the driver or is it the car or is it the size of the tool kit or the size of the budget or something?' but no, he was good.

"Even the Stig said - in Stig language, which only a few people can understand - that he was phenomenally good at driving even an old snot-box like our reasonably-priced car, and he was only 22 then."

The identity of the Stig has been closely-guarded and the subject of intense speculation ever since the show's debut, with only Perry McCarthy's admission that he was the first Stig in his autobiography 'Flat Out, Flat Broke' in 2003 blowing the cover - until a new Stig was appointed, at least.

"It is remarkable that we've managed to keep his identity secret for this long," May acknowledged, "and the way the producers have done this is that there is effectively a clause in the Stig's contract that says if his identity gets out, he has to be fired.

"This is what happened to the first Stig. That means the onus is on the rest of us not to reveal who he is, because then he would still be fired, but it would be, say, my fault - and then he'd come round and kill me!"

May - affectionately nicknamed 'Captain Slow' by fellow Top Gear presenters Jeremy Clarkson and Richard Hammond - also spoke about the former's controversial recent joke about lorry drivers killing prostitutes, which received widespread condemnation, particularly coming as it did in the immediate wake of the Jonathan Ross and Russell Brand telephone scandal.

"I'm not sure where it came from," the 45-year-old reflected. "There's obviously a popular myth about lorry drivers murdering prostitutes and it must be related to a news story from long ago, but I've either forgotten it or I missed it. We did put it through the compliance lot, and they said it was okay. Lorry drivers are free to go and kick Jeremy's head in if they see him by the side of the road!

"I don't think we debated it, and I wasn't really surprised it went in. It's exactly the sort of thing he'd say; it's Jeremy - he's being bombastic. I don't think anyone believes he actually means it. He doesn't think for a moment that all lorry drivers murder prostitutes. He's being deliberately fatuous; it's what he does."