There are moments when male-female relations plumb such depths of dysfunction it’s a flipping miracle the species lines up in breeding pairs at all. Another one happened last week.

John Cleese’s girlfriend, as she was at the time — a Californian blonde vegan called Barbie Orr, a lady of appropriately Mattel-like dimensions: ie, tiny waist, improbably big boobs, straight and shiny yellow hair — gave an interview to a newspaper about their three-month-old relationship. Actually, maybe I should come to a screeching halt right here. Many men will not even use the r-word, let alone in public, for at least a year (my husband and I have been married 16 years and we have never used that word) so Barbie had already crossed the Rubicon. But bear with me. It gets worse.

In the interview, Orr made much of their age gap — she is, or purported to be, 27 — and of Cleese’s advanced years. The gist of her witter was that although she was a total hottie and he was a scraggy grandpop of 69, he was still cutting it in the trouser department. I am going to quote directly from her interview, so those of a delicate disposition may wish to look away now.

“I kept picturing him naked,” Orr revealed. “I wondered what someone that old looks like and would I actually sleep with them. For his birthday I was thinking about buying him a Zimmer frame! He was going to New York the next day for two months and I thought, if he has a piece of this, it will seal the deal — and I’m sorry, but it did.”

Then she continued. “I can’t get into what he really looks like naked,” she said, to worldwide relief.

But then, of course, she does.

“But for an old guy, you know, they’re normally saggy down there, but he really has a nice package. He takes a lot of vitamin supplements and eats really well and he works out. His arms are really muscular and he still has amazing legs. He’s had his teeth all redone and he recently got hair plugs to cover the bald patches at the front.”

By now you can probably guess the rest. He called her up and said, “Darling, you’re The One. As soon as I’m shot of Alyce Faye Eichelberger, you are going to be the fourth Mrs Cleese!” Unlikely.

What really happened next — and I have to confess I am relying on the accuracy of my bookmarked gossip sites here — was that Cleese dumped her and then her age was outed by a tabloid newspaper as 45 and the whole episode is generally so embarrassing for all concerned, one hardly knows where to look.

Look we must, though, and this is what we find.

In the week when the film of the book He’s Just Not That Into You comes to our screens, this cringeworthy episode of Fawlty Towers (the one where Barbie talks about Basil’s sac!) offers a toe-curlingly textbook example of how not to keep a man keen.

There are thousands of books about relationships on Amazon. Most are aimed at women, with titles such as Act like a Lady, Think like a Man — What Men Really Think about Love, Relationships, Intimacy and Commitment; Women Men Love, Women Men Leave; Catch Him and Keep Him; and so on. But I could find only one in the hot 100 for men — and it is called How to Get Beautiful Women into Bed. Which tells us, I think, what we already know in our hearts. Men and women often enter into, er, intimacy with totally different agendas (men want sex; women want a relationship) and are all too rarely on the same page when it comes to the state of their union.

Take our doomed couple. Barbie Orr, a comedian and bit-part actress, asked John Cleese, world-famous actor in the process of a painful divorce from his third wife, if he was attracted to her because she was funny. “No, actually I first noticed that you had a perfect arse and then I noticed your great waist,” replied Cleese, who, post-split, had already been linked to two other, considerably younger leading lovelies.

See what I’m getting at? However swell things briefly were in the bedroom, the couple had what Shane Watson, the author of How to Meet a Man After Forty, terms “communications incompatibility”. As she says: “Women are keen on keeping it real. Men aren’t. It shrivels their extremities. So does making any public assumptions you’re a couple. She might — possibly — have got away with describing his knackers in a year’s time. But not now!”

Basically, men and women have a very different level of tolerance when it comes to talking about relationships at all, so broadcasting any details about it, let alone putting way too much information into the public domain, is bound to end in tears — the bloke dumping her by Twitter or simply not replying to her increasingly hysterical texts.

There are exceptions, of course: Simon Cowell wasn’t heard to protest too loudly when Sinitta, the singer, told ITV that he was “11 3/4 out of 10” in bed. Nor did it do David Beckham much harm when Rebecca Loos claimed in Zoo magazine that he was “generous” in bed and his rating was “8, 8 1/2. And very confident. It’s nice when a man’s confident in the bedroom”.

They are exceptions, though. Otherwise, the message of the book, the movie of the book and the tale of Barbie and Basil is all too clear: follow the rules.

Don’t call first. Don’t let him hear you debating the colour of the grosgrain trim on your bridesmaid’s slippers, or change your ringtone to Beyoncé’s Single Ladies (Put a Ring on It), or get him to discuss the names of your unborn children on the first date. And, whatever you do, keep your trap firmly shut when it comes to your sex life.

So don’t be a woman who shares too much. Do that and you’ll find out in a New York minute that He’s Just Not That Into You, not any more.

Apparently, women dyeing their hair blonde is the latest sign of recession, along with the following: eating a Subway, dining at Pizza Express, buying piggybanks to keep our money in, listening to the Today programme on Radio 4 and Wake Up to Wogan on Radio 2 and subscribing to Sky (I am not brown-nosing - BSkyB is having to hire 1,000 technicians to keep pace with demand).

The celebrity hairdresser Andrew Barton has highlighted (boom, boom!) a 67% surge in the sales of his blonde hair products compared with this time last year. “I don’t believe it is purely a coincidence that there’s been a huge sales rise in blonde hair products during these tough financial times,” said Barton, a former British hairdresser of the year.

I’m thrilled — no one saw this coming, but at least we’ll all know when the recovery is in sight: don’t look out for green shoots, but dark roots.

rachel.johnson@sunday-times.co.uk

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