At a dinner a week ago, I was sitting next to a woman who is a mother of four. She is also a slow “phwoar” of pulchritudinous lubriciousness and a national art-and-entertainment broadcasting legend. As usual at formal dinners, where the waiters hover with binary offerings of red or white, brown or white and black or white, we chatted about the one fail-safe topic open to middle-aged, middle-class people, wearing dinner jackets and long frocks, who have been seated next to each other on the whim of the placement fairy. We smiled, took a deep breath and sullied each other’s ears with mucky talk.

I don’t know exactly when it was that small talk went sexual. I expect it’s like suicide: those who talk about it don’t do it. (And before the Samaritans call me to say that people who talk about it do do it, and unless I take it back right now, they won’t be responsible for their actions — I know.) But people who’ve had their hair done especially, whose phones are on vibrate just in case nanny calls, who give more money to charity than they pay their dailies: these people talk smutty.

When you’re young, and you ache and strain to do a charade of “we plough the fields and scatter” on the wriggling body of the person next to you, you talk about Kafka or about how much better Eisenstein is than Ridley Scott. But when you reach an age where even considering having sex with someone for the first time would need at least a month’s warning, a gym, a chiropractor, an optician, an orthodontist and probably a psychiatrist, and still fill you with enough anxiety to shrivel the libido of a drunk centaur at a jockey’s wedding, then what you talk about is sex. And not just euphemistic, nostalgic, kiddy-named, petty sex, but proper, dark-side, bite-the-bedpost humperama with all the trimmings (trimming, by the way, is how they say it in Yorkshire).

We all grew up in the 1960s and 1970s, when talking about sex was a social and political obligation. The people who didn’t talk about sex were the ones who were weird about it. They were also the ones responsible for all the evil in the world and Ted Heath. So, we still talk about sex, but now it has become polite, a one-lump-or-two conversation.

My dinner companion said she was keen on talking about sex to her children; explaining it all to them in wholesome, happy terms before the smut of the schoolyard fills their little orifices. “I want them to know it’s all all right and lovely, and not to feel dirty or guilty or secretive. Have you had the sex conversation with yours?”

And, with a jolt, the image of a horrified and disgusted Ali and Flora flashed in front of my face as I heard a disembodied voice say: “Darlings, I want to talk to you about the magical journey of Master Sperm, who goes to meet Miss Egg.”

I am a wide-eyed, fundamentalist libertarian and an unreserved freedom-of-speech merchant, but I really and truly think we’ve got it all wrong when it comes to talking to kids about sex. We want to tell them how lovely, warm, caring and respectful it is — the best thing in the world — because we think that will make them responsible and careful. But if someone told you there was this stuff you got for free that was even better than a chocolate fountain laced with class-A drugs, would your response be: “Oh, well, in that case, I’d better wait until I finish my A-levels before trying it, then only do it very occasionally, within the confines of a mutually committed, loving relationship”?

The real reason we want to talk about sex to kids is because we want to stop them doing it. We know that a grown-up’s smile is the kiss of death to anything in a teenager’s life. We offer them all that beige, huggy guff and make it sound like a cross between alternative therapy, social work and keeping potted plants. No, my new year’s resolution is that I’m going to give up talking about sex, especially to those who’ve never had any. My advice to my children is: it’s frightening, dirty, weird, laughable, there’s nothing like enough of it, and the guilty secret is ... those are the good bits. If they have any questions, well, my one-size-fits-all answer is: suck it and see.

There has been a remarkable response to that thing I wrote about service charges the other week. I may be vain enough to sit down and write in public, but I’m not really mad enough to imagine any of you actually pay much attention. On the few occasions that anyone connects the paper me with the fleshy me, they invariably say: “God, you made me laugh last week. What was it? Christ, it was funny. It was that thing. You know, you wrote. I read it out. God, what was it?” Nobody ever remembers — but they do seem to have remembered the service charge.

Almost all the response has come not from customers, but from restaurateurs and waiters. And they have, in general, been supportive of making this a crusade — or at least making tips transparent. One maître d’ pointed out that you pay a service charge on the Vat and, if you drink a £100 bottle of wine, which probably has at least a 200% mark-up, you’ll pay 12.5% on top of that.

So I was impressed when they brought the bill at Cecconi’s and had already removed the service charge without my asking. It was good to see they were paying attention. The new remake of this popular Italian art-dealers’ restaurant in Mayfair is a great improvement. It has a new bar and more comfortable, if rather crammed, tables. The Blonde thought the atmosphere was a bit like New York. It’s owned by the Soho House group, which specialises in making rooms hum with a soigné metropolitan expectation. The menu’s not at all bad: a bit Now That’s What I Call Food, a mix of Italian and English with added tapas and a roast trolley.

In a previous incarnation, Cecconi’s got one of the best and most famous reviews from Craig Brown when he did this column. It was about a half-grapefruit that cost £8. The place used to be astonishingly expensive. Now it’s just quite expensive, with starters about £9 and main courses about £19.

My starter, tuscan bean soup, was rustically made and simply flavoured with rosemary. The lamb off the trolley was very welcome and better than the usual slices of fillet or bloody cutlets. But the food itself is really only a part of what they’re offering. This is a sophisticated meeting place in one of the best locations in central London.

I have heard that the service can be dilatory and high-handed, but for us, it was perfectly attentive. Well, you might say, it would be, wouldn’t it? But I like to think it’s because they’d removed the sure thing of the service charge. Tips, like sex, are all in the expectation.

5a Burlington Gardens, W1; 020 7434 1500

Mon-Fri: 7am-1am; Sat: 8am-1am; Sun: 8am-12.30am

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