In a city where the dining public is notoriously fickle, longevity is to be prized and survivors saluted. Running a restaurant is a tough business and only the brave will persist.

Ladies and gentlemen, may I present a couple who’ve not only survived but thrived. As has their marriage. Michael and Judy McMahon.

They met when working in the hospitality industry, hooked up when working as waitpersons at some of Australia’s most admired restaurants, opened their own and then, 24 years ago planted their flag outside what is now Sydney’s quintessential upscale diner, Catalina at Rose Bay.

What a story this site could tell. From 1938 it was the Sydney touchdown for the legendary Catalina flying boats, amphibious passenger aircraft of the 1930s and 1940s and one of the most widely used seaplanes of World War II.

In 1957 the site was acquired by colourful Sydney identity Jim Bendroit. Born in Canada, he worked as a stoker on a ship to Australia, landing here in 1910 with just five quid in his pocket. Back in Canada he’d been a star roller skater.

Tall and handsome he also took to ballroom dancing and embarked on a career in show business.

Later he was to become better known as restaurateur and gentleman of the turf. A plunge on a filly called Gay Romance gave him the funds to open one of the two great restaurants of the late 1930s (the other was Romano’s) and in 1956, he acquired the site of the Catalina base and built over the water a glamorous eatery called Caprice.

Such was the fame of Caprice that when Arnaud de Rosnay, a swashbuckling young French aristo with a major fortune, a string of beautiful girlfriends including the actress Maria Berenson, and a burgeoning career as a fashion photographer, was invited to do a spread on Australia in Vogue, he opted for a shot of Caprice to embody the idea of a sophisticated Sydney nightlife.

With Bendroit’s death, Caprice was old to an American expat businessman rumoured to be a CIA plant, and it slid into genteel desuetude and the young McMahons pounced and over the past couple of decades have transformed Bendroit’s baby into the most glamorous and consistent waterfront watering hole in town. The McMahons are now in the midst of what they have described as a “very difficult” process in securing a $5.2 million expansion that would double the capacity of Catalina from 94 customers to 200. The Woollahra Local Planning Panel deferred its decision on approval in late March, declaring it required “further evidence” to address concerns over whether the expansion met the Lyne Park site’s existing use rights and environmental regulations before it could rule on the application.

Michael McMahon, now 65, was born in Concord West. His father, who had been a long-term employee of the Anthony Hordern mega retail emporium on Brickfield Hill, retired to a hotel in Cootamundra where his son worked for a time before moving to Sydney to work for Len Evans in Bulletin Place.

Judy, 62, is a New Zealander. “I went to Wellington University in the days when education there was free. I didn’t do it because I thought it was going to lead to a job. It was self-improvement and independence.” With a bachelor of arts degree under her belt, she too took a job with Len Evans.

The McMahon romance took some time to kindle. Attraction was hardly instant.

“I thought he was the flashiest bloke I’d ever met. I didn’t like him at all. Far too confident,” recalls Judy.

Things must have changed quickly for soon they were a team,

“When we had Barrenjoey House we both worked on the floor and if I may say so we were bloody good,” says Mrs McMahon.

Guests will attest that they were bloody good too when working together in what was perhaps the most influential restaurant of its kind in the country, Tony and Gay Bilson’s ground- breaking, Glen Murcutt-designed Berowra Waters Inn overlooking a branch of the Hawkesbury River.

Anders Ousback played a Cupid role in the affair in that it was he who lured Michael to Berowra.

“My first interest was in wine. I had thought of going to Adelaide to work in wine industry but Anders said: ‘What? So you want to be a bloody farmer’.

“I had never heard of Berowra Waters Inn so I looked it up and saw that it was regarded as the best restaurant in Australia. So I went. I’d never waited on tables, never done anything like that. After the third week he told me I had the job,” adding, “I’m going to London next week. You’re in charge from now on.”

And thus began one of the most durable and successful life and career partnerships in the Australian hospitality industry. And talk about keeping it in the family. The McMahons’ two children, Kate and James, have taken to the business like seagulls to the surf. Jointly and severally they run front of house at Catalina with polish and aplomb. And Michael’s son by a former marriage — “He’s my son too,” declares Judy firmly — worked for a couple of years as a cook before deciding on a shift to photography. “He’s very involved,” says Judy. “He does all of our photographs including all the images for Instagram.”

Her firm opinions, thoughtfully expressed, seem to act as a counterbalance to his forcefully stated views, particularly on the state of the restaurant industry. Should you wish to get this dander up, just ask a question about fine dining. Received opinion is that fine dining is on the way out.

Perish the thought. McMahon lets fly. “I absolutely hate the idea that we’re seeing the end of fine dining. I find the whole idea of it ebbing dead is hideous. It’s just a way for hipster restaurateurs to cut corners. I hate sitting down to a table without a cloth and places badly set. I hate noise and I hate waiters in shorts. I was in a restaurant the other day and the waiter came up to me and said: ‘G’day mate. What can I do for you?’”

Bridling, McMahon said: “First of all, you’re not my mate and unlikely ever to be one. You can’t do anything for me. And I got up and left.”

One cannot but admire such uncompromising standards. And the McMahons are as committed to them as they are to their family and their business. Their restaurant is run along Prussian lines. Efficiency and professionalism are evident in details from the starch in the napkins to the sheen on the silver and the sparkle of the wafer thin glassware. And of course in the notion of service. Catalina is the only class restaurant in Sydney open 365 days a year.

Our lunch is the day after Mother’s Day and the inevitable invasion yet the place is running as smoothly as a Rolex watch. The food is impeccable, the roast suckling pig sublime, the chablis as sunny as it is outside on the harbour. In my opinion there are two restaurants that make a Sydney dining experience unique. One is the funky Sean’s Panaroma. This is the other. What they have in common is unswerving dedication to making dining as pleasurable as possible.