After Lady Glenconnor, the former lady-in-waiting to Princess Margaret, recently declared that the use of fish knives is distinctively middle class, William Hanson, an etiquette expert, revealed the other telltale signs that you are "common".

In response, thousands of you Telegraph readers wrote in with your own.

For Nicholas Swann, it's "saying to a customer, 'alright my lovely', rather than, 'good morning, Sir'".

Meanwhile, Ali Heyes, weighed in, saying: "Buttering a whole bread roll. It should be broken bit by bit and butter applied from a small amount which is on the side of your plate."

"Using the word 'get' when you order a drink," was a big no-no for Gavin Charlton Brown.

Mel M. took issue with the use of the word "toilet", which she thinks is "just pretentious and is actually what you do when you get there". She prefers "loo, lavatory or even bog".

Linda McDonalds-Brown insisted that: "Any colour other than white for your loo rolls is very lower class."

Nevertheless, from prosecco in lieu of champagne to mounted televisions, there were a number of "common" signs that Telegraph readers disputed.

Despite Lady Glenconner's pronouncement that fish knives are for the unrefined, David Eades rebutted: "My great aunt was given a present of some silver ones for her wedding after the First World War by Lady Olein Wyndham-Quin, a daughter of the 5th Earl of Dunraven.

"Obviously she had no taste!"

According to Catherine McMahon: "The purpose of a fish knife is it is designed to pick delicate fish away from the bone, same as a steak knife is designed for cutting through steak with ease.

"Not quite sure why the aristocracy thought of that as being 'beneath them'."

Similarly, Christopher Entwistle still has his granny's fish knives because "they are actually quite practical as the curved blade facilitates the removal of the flesh".

"How else do you fillet a grilled Dover sole at the table?" questioned Richard Brown. "There's nothing wrong with fish knives and forks."

According to Mr Hanson: "In recent years, the drink has moved into the ranks of the blatantly middle class."

For Peter Watson, it's not gin and tonic that's the problem, but "the tonic if it isn't Fever Tree".

A number of readers also disputed the way in which Mr Hanson suggested a gin and tonic should be served: "With a good ice cube, a decent glass, a slice of lemon and tonic water."

Nicholas Millman shared his choice: "For real refreshment, I prefer lime to lemon in my 'common' gin and tonic. A little juice as well as a slice, and with ice and the tonic from the fridge, which both add zest.

"Nothing worse than the tepid, or even warm, rather flat gin and tonics with those bedraggled slices of lemon sometimes served in commercial establishments."

Ron Yates agreed: "A G&T should be with a slice of lime, not a slice of lemon (as suggested by Mr Hanson). Perhaps he is unaware that it was the unavailability of limes during WW2 that led to lemon being used instead?"

And Joe Woe strictly enjoys a G&T as follows: "Gin of one's choice, two ice cubes, no fruit, definitely not with an umbrella or a stir stick, and a tonic of choice on the side. That's it."

Mr Hanson advised against purchasing televisions larger than 46 inches, describing anything beyond that as "suspect", particularly "massive 100-inch televisions". He also stressed that wall-mounting these screens only makes one more common.

Yet Telegraph readers had differing views.

Luke Tones quipped: "Forty-six-inch TV? Can you even buy them that small?"

Mark S. couldn't understand "why anyone with the money and the space wouldn't want to have the largest screen they could get".

"And if you do have a very large screen, it's better and neater to mount it on a wall than to stand it on a piece of furniture," he said.

Mark T. said: "My TV is mounted at the perfect height for viewing from the sofa. It's used for watching TV, movies and gaming. Why choose to have a smaller screen than you can afford? Choosing a small screen for pretentious reasons makes no sense at all.

"I'm more of a function-over-form person rather than pretension over function."

When it came to hand hygiene, Mr Hanson asserted that "no liquid soap is upper class".

According to Telegraph readers, however, a bar of soap is terribly unhygienic.

Liz Kershaw claimed: "Using liquid soap (Aldi's is fine) rather than a bar is better for cleanliness."

Likewise, Andy Jack said: "Any liquid soap is preferable by a bathroom sink for handwashing. Bar soap in a public bathroom is a filthy thing."

Brett Wilson was in agreement, saying: "If I've been cleaning horses and the tack or after doing the garden, I like liquid hand scrub otherwise my hands get dry."

Barbara Fisher also "loves" liquid soap compared to "those dirty cracked bars of soap".

Hot tubs are similarly a "common" sign for Mr Hanson, as he said: "There are few accusations worse than one can level at someone that they own, or that they aspire to own, a hot tub.

"You're just getting into a Petri dish of filth whilst microscopic chunks of their epidermis flow past," he explained.

A number of hot tub-owning readers opposed Mr Hanson's view.

One anonymous reader praised "the incredibly relaxing hydro-massage" they receive when using their jacuzzi.

"Mine is, obviously, not on the outdoor terrace, but discreetly in the indoor swimming pool complex. We have an effective filter on ours for the 'microscopic epidermis' and certainly no coloured lights. It's heaven!"

Andrew Carnegie's "swim spa (a type of large hot tub) defies the description given". He described how "the water is determined to remain crystal clear throughout the year, although it's mainly used only by my wife and I, which may help."

Mr Hanson said that if you really want champagne "but you either can't afford it or there isn't any", that's when choosing prosecco becomes common.

Telegraph readers, however, disagreed when it came to drinking some fizz.

Stephen Wilson said: "Cava or prosecco are just as good as champagne. But then I don't have any pretensions."

Andrew Wilson pointed out that prosecco is not, in fact, a substitute for champagne. "Unlike cava, it is not made by the champagne method," he said.

David Ball revealed that the reason he drinks prosecco over champagne was nothing to do with cost.

"I order prosecco not because I can't afford champagne, but because I don't like the taste of it. It's hideous!" he said. "So ordering prosecco has nothing to do with price or affordability, but everything to do with personal taste."

"You're drinking the wrong prosecco", remarked Esme Weatherwax. "A good Treviso, or better still Valdobbiadene, will change your mind."

In the end, it was Elizabeth Hopkin who cut through all the fuss: "Being posh is like being cool: if you wonder whether you are, you probably aren't."