How flattering to have the world's best newspaper dedicate an issue to our very own capital city. For any Americans reading, I mean that entirely without irony. The New York Times Magazine's "London" supplement that appeared on Sunday was a beautifully photographed, earnestly researched cultural brochure for Manhattanites who have bought their Olympic Games tickets and booked rooms at the Dorchester, but remain anxious not to make a faux pas this summer.

It opened with an essay pitched at the Wall Street financier: "You might be surprised to find that the central node of global finance... is London, not New York." Jaw slackened at this revelation, the American reader was then invited to pore over a lengthy crib-sheet – with charts and bite-sized factoids – on how to "get" London and its habits.

So what did the journalists of the most rigorously fact-checked newspaper in the world get right – and what, more amusingly, did they get spectacularly wrong?

On the whole, our attitudes and prejudices were pegged pretty accurately. "Londoners don't support Manchester United, or visit Angus Steak Houses," sounds true enough. But on the subject of infrastructure, "things work, but don't work" is unarguable. Americans like to think of London as medieval in its efficiency, and if you've ever waited 12 minutes for a District Line tube at 9am, you tend to agree. Meanwhile, Londoners are "absolutely not" "psyched" by the prospect of the Olympics, because by nature we're "affronted... that any future happening is going to be profitable, transformative or, worst of all, pleasant." True.

Finally, in a lexicon of Londonite expressions, the reader was informed that "I'm not being funny, but..." always introduces a socially unacceptable statement. Again, factually correct – although aren't Americans often guilty of using apparent courtesy to be very, very rude?

And now for the errors. London is, said The New York Times, "a place where everyone drinks, all the time". Oh that it were so. Perhaps, some time in the 1940s, when the GIs were still here, Londoners did drink gin for lunch and pregnant women sank pints of Guinness. But social teetotalism has been imported from, er, America, and religious abstinence from the Middle East: late on Saturday night, I walked through Kensington past empty pubs and full-to-bursting coffee shops, where cake and tobacco are the only indulgence. If New Yorkers want booze tourism, they're better off in Paris, or Tokyo.

Also badly out of date is the assertion that Londoners are "convulsed by courtesy, embarrassed by display". Perhaps the doorman at the Dorchester apologises if he accidentally jostles you with a Vuitton holdall, but on the streets at large it's no longer true that "saying sorry" is a reflex response; rolled eyes and a scowled "what's-yer-problem?" is more likely.

Neither could I agree with the magazine's predictable paean to the intellect of the black cabbie, particularly that all of them are familiar with London's 26,000 streets; unless you're going to Leicester Square, the passenger who jumps in the back with neither A-Z, smartphone nor familiarity with one-way systems near his destination is as good as lost.

Most bizarre was the advice that the item which could best illustrate the notorious expense of London, a "true barometer of economic behaviour", was the price of a box of imported Lucky Charms (a kind of sugary American cereal). Apparently, they sell for $14 in a Notting Hill grocery.

Believing this to be typical of the cost of eating in London could lead many an innocent American to make an expensive mistake. And – this is something The New York Times was too polite to mention – this summer, there'll be no shortage of unapologetic London shopkeepers, hoteliers and cabbies to help them make it.

s.rushton@independent.co.uk