But get into an interview room, and witness the change. Would Bob have made it as head of a merchant bank? Could Gazza have welcomed first-class passengers aboard a BA flight as a pilot? The evidence suggests not. Speech therapists are reporting a healthy demand from employees in the commercial and professional worlds willing to put their accents under the elocutioner's axe. And five years after the Kensington finishing school, Lucie Clayton, set up its accent course, clients are still flocking to it.
Evelyn Brunner, a speech therapist in Manchester, has witnessed an increasing demand for help with accents and grammar. "We used to call it elocution; the word went out of favour, but now it is very popular again," she explains. "Our big management and executive people are travelling now, not just to London but abroad. Londoners openly make fun of northern accents and my clients conclude they're not going to get as far as their ability should take them. Vocabulary - the lack of it - can be a problem, but it's mainly the accent that bothers them.
"I work a lot with trainee solicitors. Solicitors with regional accents feel unconfident in court. Also, clients expect a professional to speak better than they do; they want to look up to them."
The accent to get you that job is finely modulated RP. Think Michael Buerk. The Queen's English - "overly refeened" - is out. What you want, says Brunner, is "a good clear, authentic English, preferably without any tag from where you came from. It will take you anywhere and people will know you speak well."
It took Sandra, aged 27, who is a television researcher, a year to change her accent. She judged that Cockney was okay for comedians or taxi drivers but not much else. "Janet Street Porter once said that her voice made people label her as working-class and a `cheeky kinda person'. I really identified with that. I got a job at 19 as a secretary in an independent television company and it was there that I really started thinking about the way I spoke. I was quite ambitious and I saw changing my accent as a career move, like wearing a colour-co-ordinated power suit or reading the right newspaper.
"I speak every day on the phone to people from all walks of life, some quite upper-crust. Having a standard accent freed me from judgements people would have made about my competence had they heard a Cockney twang." Sandra sometimes worries that her decision was a selfish one, that she has made it tougher for young people with regional accents who are coming up behind her.
"I admire Glenda Bailey, the former editor of Marie Claire, for not changing her accent," she says. "Her `close-your-eyes-and-it-could-be-Vera-Duckworth' voice is just not what you expect from a high-profile magazine editor and she gets some stick for it. But I'm afraid I'm a conformist. I'm not that confident."
As a journalist, I have encountered many people who have swapped their accent, but everyone I approached for this article fought shy of being named. No one wanted to be thought pretentious. One BBC executive producer admits his "thicko" West Country accent had to go when he went to Oxford. One 29-year-old Liverpudlian doctor admits - coyly - that he deliberately knocked the edges off his accent at 16 by studying the Nine O' Clock News.
You've got to be dedicated to change your accent. "If you've got a keen ear," explains Brunner, "you pick it up quickly from people around you who speak well. Speech therapists can help by using jingles - exercises like saying `my f-a-ther's c-a-r is a jagu-a-r'. It's overdone to get the right sounds. You've got to give it a year or two, you can't do it drastically - too sudden a change would make you a laughing stock. It's got to be natural."
Research shows that it pays to go RP. The "right" accent gives the impression that the speaker is intelligent, ambitious and even clean. The late David McKenzie Davey, a chartered psychologist specialising in executive assessment, found RP women were thought to be more confident than women with non-standard accents, and were rated as more adventurous, independent and feminine.
Where does all this prejudice come from? Surprisingly, it is not that old. "It's probably because of the public school system," says Paul Coggle, senior lecturer in modern languages at the University of Kent. "Once we had regional accents throughout the United Kingdom - even the aristocrats spoke with a regional accent and it was perfectly acceptable." When the public school system really took off in the last century, aristocrats sent their sons to them, "and this prestigious accent developed on a non- geographical basis which immediately excluded people who hadn't been to the right schools".
Our disdain of regional accents is rooted in history, too, according to many linguists. The accents come from industrial cities associated with squalor, grime and getting your hands dirty. The bad speech guide goes like this: Glaswegian makes people run for cover - it's the equivalent of a crew cut and a snake tattoo; cockney denotes dishonesty - it scores low on the "would-you-buy-a- second- hand-car-from-this-man?" list. So what accent is acceptable? Not West Country, that's for sure. Look at poor Louise Yates, wife of footballer Steve Yates taunted for being a "wurze" when she moved from Bristol to Surrey. Yorkshire? Yes. Friendly, honest, frugal. Which is why hundreds of local men and women are talking themselves into jobs in financial services. One reason First Direct set up in Leeds in 1989 was the public's love of the accent, and it's home to the AA information office as well as the Alliance & Leicester's telephone banking service. Home delivery firm Freemans is planning to move its customers' HQ from Stockwell, London to Sheffield next year after a survey which found the accents conveyed the right image - friendly and efficiency.
Birmingham, though, is possibly the pits. It says white socks and grey plastic slip-on shoe's. Dr Clive Upton, from Sheffield University's Centre of English Cultural Tradition and Language and editor of An Atlas of English Dialect, comes from south Birmingham. His beloved city never gets a good press, he says. "It's never had a regional status in the same way as Newcastle or Manchester. It's only 100 miles from London, it's the second city and people like to put it down, like the rejoicing when it doesn't get the Olympics." What it needs, he reckons, is a Brummie equivalent of Jimmy Nail or The Beatles to give it a bit of kudos.
All of this is hideously snobbish but it is understandable, too, how hard it is to break the mould. Mr Coggle, for one, is sympathetic to demands on an employer. Few want to be prejudiced but we live in the real world. What's the point of spending a fortune on letterhead logos and boardroom furnishings to project the right image of sophistication and efficiency and then hiring a receptionist whose voice says to callers bleached highlights and white stilletos?
Mr Coggle, though, is hopeful for the future. He senses changes in the air. Increasing numbers of young people up and down the country are embracing the more egalitarian Estuary English. Many of his university students identify with City-based accents, be it Brum or Scouse. They enjoy the street credibility and shy away from RP.
"Some of my friends say their off-spring talk RP to them at home because that's what they want to hear, and talk Estuary to their friends," he explains. "In my experience with the 18 to 24 age group, those who are looking for jobs are aware that in an interview they need to modify their accents towards RP, and they are able to do so."
We already have John Major, and Mr Coggle forsees a time when we might be ready for John Prescott as PM. A King of England speaking Estuary? "That will take a lot longer than 10 years," he concedes. "The Queen still says `orstralia' for `Australia' and `get orf the bus' - or would do if she ever got on one. Charles isn't far behind her. Di, though, is always aware of the `common people'; she wants her accent to reflect that, and it does. "The media's changed a lot too, but the last bastion is the news. They now have black newsreaders, which they didn't 15 years ago, but only so long as they speak RP. The day we have a newsreader on national news who has a regional English accent, then a bastion will have been stormed."
And which accent will crush the mighty edifice of snobbery? "Oh, I think Brummie," laughs Mr Coggle. "And if you think of it, Sue Lawley was brought up to speak Brummie. She's made her mark, is highly respected, but she had to move to RP. Now I think, even with all her respect, if she went back to Brummie she would lose favour." Now, there's a challenge. If you're reading this, Sue, voice coach Evelyn Brummer is out there waiting.
Have they, haven't they?
some people change their accent:
Sue Lawley Shirley Bassey
Peter Andre Richard E Grant
Selina Scott Joanne Whalley
and some stay true to their roots:
John Cole Janet Street-Porter
Accents: an `elp or an `indrance?
Terry Christian, TV presenter: "Accents come from a `them and us' scenario tied in with class - a listener once said I had an `awful left-wing accent'. Manchester was incredibly hip back in `89 and `90, and it helped me get the job presenting The Word. Otherwise, because TV and radio is run by ex-public school types who employ people like themselves, anyone working in the media who has an accent, especially a non-Home Counties accent, immediately sticks out. This is even though only 3 per cent of the population speak RP."
Susan Ferleger Brades, director of the Hayward Gallery: "I left New York 18 years ago, but my accent's stayed. It hasn't held me back as far as I know and I've never been advised to change it. In fact, it's been a bonus in that I can say things that English people may not dare to."
Jon Roseman, theatrical agent: "RP was always such a BBC thing. It was part of that establishment, bow-ties thing. Today things are a lot different - as soon as American accents became acceptable, so did others. As long as a regional accent is not too heavy, it's not an issue any more. The main thing is that people speak clearly."
Wayne Hemingway, chairman, Red or Dead: "When I worked on a London market stall my Lancashire accent got me remembered. But in the Eighties the fashion press treated me with a certain amount of suspicion and this, I think, was due partly to my accent. It's only in the Nineties that that whole plummy mid-Atlantic thing became naff; now it's fashionable to be yourself."
Patsy Rodenburg, voice coach, National Theatre: "Any accent is valid in the theatre, but a great body of work is written for RP, especially at the moment. RP is very useful as people all over the world can understand it - it's neutral. People tend to link RP to confidence. It is a very energised form of speech, it's very `forward' in the mouth and it's very healthy for the voice."
Stefanie Callister, newsreader, Sky News: "Most people find accents acceptable nowadays. I was BBC-trained in Belfast for 7 years - they knocked off the rough edges off my accent. I've never been advised to speak RP - Terry Wogan and Gloria Honeyford had already paved the way for Irish accents. I think a Celtic accent is far more acceptable than a dodgy London one."
Interviews by Cayte Williams