"TOP GEAR", an inexplicably popular television programme in which three paunchy Englishmen drive slender foreign sportscars, recently began a new series in Britain. The BBC, which makes "Top Gear", is short on money . How do you think they decided to generate some publicity on the cheap?One of the oldest ruses in marketing is to create a controversy that generates more exposure through newspaper column-inches than you could hope to buy through conventional advertising. Having your album cover banned , for instance, is the surest way to get people to Google it.In this spirit, the writers of "Top Gear" scripted a two-minute section of this week's programme in which the braying presenters made a series of rude comments about Mexico. Richard Hammond, one of the show's presenters, observed that Mexican sports cars were like Mexicans themselves: "lazy, feckless, flatulent, overweight, leaning against a fence asleep looking at a cactus with a blanket with a hole in the middle on as a coat." In case the ploy wasn't obvious enough, they ended by saying that they wouldn't get any complaints, “because at the Mexican embassy, the ambassador's going to be sitting there [asleep] with a remote control... They won't complain, it's fine.”Of course, the Mexican ambassador did complain. In a l etter to the BBC , he described the show's comments as "offensive, xenophobic and humiliating". The tired old programme has now got itself a mention in every British newspaper. Mission accomplished.Or not? The clip has reached the Mexican papers' websites too. "Top Gear", to the eternal embarrassment of Britons living in Mexico, is very popular here. But one network of radio stations has already said it will boycott BBC content in protest. This week's stunt might have gone down well in the domestic market (population: 62m), but it has been an own goal in at least one export market (population: 112m). How long before the "Top Gear" PR machine crunches into reverse?