We are a nation of dodgy-mannered eaters

In the technological age, modern dining etiquette is about so much more than just keeping your elbows off the table.

Midday on Saturday at a restaurant in London. Two lunchers, both men in their twenties, sit in the back corner. The starters are on the table. One is fiddling with an iPhone, giggling at the screen. The non-fiddler leans forward. Bent across the table, he points a fork, complete with prawn, at the iPhone, making threats as to its continued well-being if it continues to enlighten and amuse.

"Ok, fine," says the fiddler, bored, "but everyone does it, you know?"

I can recount this bit of the conversation because the non-fiddler was me. The fiddler was a schoolfriend whose iPhone remains fully operational, so my bluster clearly disappeared like the hot air it was.

Does this, my bit of manners vigilantism, make me pompous? A droner who can't amuse himself in a restaurant for a couple of minutes? A male Hyacinth Bucket in skinny jeans? Maybe so. But few would deny and indeed my friend did not deny, that it was rude; an ill-mannered thing to do at the table. It's not that I think people enlightening themselves as to Joey Barton's latest Twitter missive are going to claw at the foundations of civilisation (civilisation seems to be ticking along just fine) – it's just as there were only two of us, I thought, you know, we might have a chat.

If there had been three of us, fine. I could have spoken to the other person. But there weren't. And anyway, being dropped for Joey Barton is wounding. And at lunchtime that just isn't on.

On one point, though, my friend was on the mark. Everyone is doing it. We are a nation of dodgy-mannered eaters. "Go into a busy restaurant at dinner and look around," says Sean Davoren, impeccably mannered head butler at the Savoy and author of Manners from Heaven. "You see people eating bits of chicken with their hands, people not placing their knife and fork back on the plate when they are finished (how is anyone supposed to know they're done?) and people eating with their mouths wide open. Or, the height of bad manners, answering the phone or an email mid-meal – that sort of thing is really on the rise."

It certainly appears that smartphones are table manners' real foe. A survey by Ofcom in 2010 revealed that 23 per cent of adults and 34 per cent of teens use them at meal times. Indeed, in response to the ever-tightening grip of "FOMO" (fear of missing out) at mealtimes, which sees sufferers checking twitter/email/Facebook with debilitating zeal, a tumblr user called Brian Perez has created a new game.

Everyone eating with you in a restaurant stacks their phones in the middle, face down, with the first person to turn theirs over picking up the whole tab. On the net it is referred to as the "Phone Stack Game" and sometimes, the writer getting to the heart of things, the "Don't be a Jerk During Meals Game".

Although they may not be phrasing it in quite that way, that seems to be the general message of the new etiquette lessons for sixth formers at Bishop Heber comprehensive in Malpas, Cheshire.

The school made headlines in December when it announced that, for an hour a week, the normal curriculum would makes way for classes in correctly eating asparagus, spaghetti and how to de-shell a prawn without looking like a fool.

It is worth noting at this point that no-one is calling for prissy over-refinement. No-one wants to mirror Julian Fellowes who, so the story goes, permits himself a smirk when his dinner guests gauchely tip their soup bowls toward them, rather than away. "That's silly," says Davoren. "Formal etiquette is an add-on to general manners. In a sense it's separate. Knowledge of etiquette gives confidence to those who know about it – but it isn't essential. The important thing is core regard and courtesy for someone, rather than knowing about all the arcane rules."

Indeed fusty, formal etiquette may actually account for our general boorishness. Formal dining etiquette smells suspiciously of public schools; a certain tie; something that can be used to keep the great unwashed at bay; you don't know the form; you aren't one of us. But that isn't manners, says Diana Mather of etiquette firm Public Image. "Manners are entirely benign. Etiquette is a code of rules, which can, indeed, exclude people not in the know – it can be archaic and complex.

"But manners are ageless, priceless and classless. They are a way of saying to someone else: I won't do this because it might embarrass or irritate you. They're an expression of regard for others and can be a leveller, in some senses."

So, it's pretty clear we know what we don't want: six-knife table settings or talking with your mouth full. But what is permissible? How should modern man or woman behave at dinner, lunch or tea? Should we be all Downton or more Henry VIII?

"The best advice is gauge the situation and do as your host does. There are some general rules, though. Don't use a napkin as a baby wipe – just try not to make so much mess. Don't encroach on other people's space or take their bread. Don't worry so much about when to talk to the person on left or right. Just make sure both get some attention. If you have to text, go to the loo and do it there. Never let technology become more important than a person," says Jo Bryant, etiquette advisor at Debretts, which publishes The A to Z of Modern Manners.

Keeping that in mind, it may be worth adding an addendum to William of Wykeham's famous dictum "Manners maketh man" It would read: "...and technology seems to undo us." Our mental behaviour barometer does seem to go haywire when it comes to the ever-connected box in our pockets. Perhaps in part because it's so new an invention (we have, after all, had time to come to grips with the tri-pronged fork), we haven't quite figured out the dos and don'ts of using it yet. So let's create a new rule, by popular consent, that renders the shrimp-pronged fork redundant.

Let's all agree to ignore Joey Barton and the Twitterati for three-quarters of an hour and invert that well-known dieters' mantra at mealtimes and say: Eat it, Don't Tweet it.

Dos and Don'ts: From the experts

The rules according to Jo Bryant from Debretts and Diana Mather of Public Image Etiquette.

You don't have to know which knife to use, but do use your cutlery properly. "Don't use your fingers, unless it's pizza," says Diana Mather.

Be polite and courteous to your fellow diners. "Do make sure you chat to both your neighbours equally. Don't give the beautiful person more attention than the old trout," says Mather.

Elbows on the table isn't a crime, but keep your hands in check. "Don't butter your bread in the air and swing cutlery. Table knives aren't meant to be weapons, so don't turn them into them," say Mather.

Don't be a stickler for traditional rules. "Don't hide behind formal etiquette. Make everyone feel comfortable," says Jo Bryant from Debretts.

"Do ask others if they want the last bit of bread. Don't eat it yourself," says Bryant.

And finally, "Turn off the phone. Or if it must stay on, leave the room when answering it," says Bryant.