But that's probably why Martin Glenn is the most influential marketer in Britain, the man given the task of making Pepsi more appealing to the British public than Coca-Cola.
Glenn has his work cut out - given that Coke currently outsells Pepsi in Britain by around four tins to one - but then he is the man who transformed Walkers crisps into the nation's number one supermarket brand.
He has even been tipped as a future chief executive of an organisation with one of the most-maligned brands of recent years, the sex scandal-ravaged Football Association.
Glenn is "a sort of Jose Mourinho without the Machiavellian tendencies" according to one review of his new DVD/book The Best Job in the World (subtitle: "Business Insights from the UK's No 1 Marketer").
But to others Glenn, 43, the chief executive of PepsiCo UK (the parent company of Walkers), is perhaps a slightly more sinister figure, the arch pedlar of junk food to a British public that is increasingly obese.
Up close in the stylish offices of PepsiCo's British advertising agency AMV BBDO, Glenn explains his marketing secrets. Slim and sporty, he coaches his 11-year-old son's football team, runs three times a week and doesn't look like a junk food junkie himself. "I don't tend to get obese but I'm not a sports freak either," he says.
If PepsiCo UK is to thrive, Glenn knows it must make greater efforts to respond to growing public awareness of the dangers of sugar and saturated fats. "If we don't we will become marginalised," he says. "We don't intend to do that. Fifty years ago Walkers crisps was a pork pie shop in Leicester; now it's Britain's biggest supermarket brand. You keep adapting and if you don't see [healthier eating] as a big opportunity, then you are crazy."
So Glenn's Pepsi strategy will be to undermine Coke's stranglehold on the UK market by skilful promotion of the no-sugar brand Pepsi Max, which the company claims has a fuller flavour than either Diet Coke or Diet Pepsi. Glenn believes Pepsi Max - which was launched in 1994 - is a "real sleeping giant". He says: "It was designed to make diet drinks appeal to blokes [but] we had sort of forgotten about it because it didn't fit in with the global footprint of pushing the regular Pepsi brand."
Now Pepsi Max is back on the company radar and Glenn says it is his key weapon. "We put all the advertising and marketing effort behind that and it's really paying off nicely. There's now more no-sugar cola being sold in the UK than regular cola. In places like Norway where we have been pushing the strategy a bit longer, our share versus Coke has improved massively."
His other plan for outflanking Coca-Cola is to broaden the beverages portfolio. Just as in the US - where Pepsi has been working its other drinks brands such as Gatorade and Mountain Dew - Glenn's UK strategy includes big plans for the Tropicana fruit juice brand and the recently acquired British crushed fruit drinks company PJ Smoothies.
He has also scored a notable victory over Coca-Cola by getting PepsiCo (if not Pepsi cola itself) into McDonald's restaurants, which have traditionally been Coke's domain. As the world's most famous burger chain responded to junk food criticisms by repositioning itself as a vendor of healthy breakfasts and salad-based lunches, PepsiCo seized its chance to get its products (Tropicana juices and Quaker Oatso Simple) on the menu.
Glenn is delighted. "If you wanted a signal as to how life has changed with respect to food and eating, the fact that you can go to McDonald's and buy Tropicana and Quaker Oats for breakfast is it," he says. " McDonald's used to be an absolute Coke stronghold."
On one level it all sounds very odd. Britain's most successful marketer of snack foods is putting so much of his energy into sugar-free drinks, fruit juices, porridge oats and smoothies.
Glenn admits that PepsiCo UK and other British-based food companies have been placed under intense pressure to become more responsible for the health effects of their products. "The British people have been subjected to almost unprecedented newspaper and government interest in their diet. That's a good thing. We are increasingly an obese nation and that's not in anyone's interest. Why was there such phenomenal interest in Jamie Oliver? Because people are interested. If you are in denial about that, you will lose it," he acknowledges.
Even Walkers crisps, which now has a staggering 45 per cent share of the £2bn salty snacks market in the UK, is having to adapt. Glenn has launched a new low-fat range called Potato Heads, a skilful marketing ruse aimed at overcoming children's deep mistrust of "diet" foods.
"We have a low oil production process which can take 30 per cent of the oil off," he explains. "We sold that as Walkers Lites for a few years and they did really well. But if you showed kids Walkers Lites they would run a mile because they think they are going to taste awful. Mums said 'I wish you'd market stuff to me that would help me get my kids to eat low-fat stuff'."
Potato Heads has branding that is designed to appeal to kids (an animated character, with the familiar voice of Gary Lineker on the television ads) but is aimed at mothers who recognise the health advantages of low-fat crisps and know this product will not be thrown in the bin.
"Big brands stay relevant by being helpful," says Glenn. " It's actually aimed at mums. The kids are quite smart: they know they don't have to use a bargaining chip with mum to get a Potato Head. Mums are happy that the kids will eat this stuff and they don't have to force them to eat the diet stuff."
Glenn's radical thinking includes a lack of respect for the notion of " above and below the line", adland's traditional distinction between such things as television campaigns and the more unfashionable work of promoting a product within a supermarket. "There's a certain breed of marketer who is quite happy to talk TV commercials all night but when it comes to point of sale then, for some reason or another, they're always far too busy."
As well as tearing down this line - or "Berlin Wall" as he calls it - and making "all marketers free and equal", Glenn believes in driving sales by creating news about products.
So Walkers generated press coverage through a Free Books for Schools campaign, which Glenn promoted with The Sun and The Times newspapers. (Empty crisp packets and clipped newspaper mastheads could be exchanged for books.) He also secured Victoria Beckham as the face of the posh Walkers offshoot brand Sensations.
He is also convinced of the value of packaging and "making sure our products look as gorgeous as they taste". Crisps used to be sold in see-through packets until Glenn's team introduced the foil pack, which stands up more rigidly on the shelf, as well as preserving the crisps better.
Customers "get sick" of the tired marketing ploy of simply stamping "new and improved" on the product. "We try to think of the brand as a favourite character in a soap opera whose story will twist and evolve over a number of episodes," says Glenn.
This explains the thinking behind the Gary Lineker "No More Mr Nice Guy" ads which, masterminded by Glenn and famed commercials director Paul Weiland, have run for 10 years, longer than any other modern British campaign. Glenn believes that a proven success is worth sticking to and that too many brand managers introduce "change for change's sake".
The concept of the Lineker campaign is so respected that it has been replicated around the world; rugby legend François Pienaar is the crisp thief in South Africa, while in Spain it is the film star Antonio Banderas. More significantly, it has made Walkers almost unassailable with 70 per cent of the British crisps market.
It used to be that Golden Wonder was the British crisp brand leader - until a disastrous fire at its factory in 1986. Many other Britons grew up with Smith's crisps, a brand which was also acquired by PepsiCo but, soon after Glenn joined the company, was merged into Walkers in 1992.
Glenn himself grew up in Tamworth near Birmingham, the son of two schoolteachers. "Neither of my parents worked in business and none of my friends seemed to either," he says.
Back in 1976 he was a sixth-former at a Catholic comprehensive when Shirley Williams, then a Labour minister, began a debate on why so few graduates chose to work in industry. Glenn's general studies teacher challenged the class to respond to an essay competition organised by The Guardian in response to Williams's comments. Glenn's positive appraisal of a career in business won him a £25 prize and a meeting with Williams. "I was the only person in my year who went into industry," he says.
This sense of vocation continued at Merton College, Oxford, although Glenn, the master seller, seems at pains not to portray himself as a high-flyer, pointing out that Oxbridge had not been his idea but that of Mr Pike, his English teacher.
After graduation he decided to join Cadbury Schweppes. "I've always been quite good with people. I can mix with a variety of types quite well," he says. "[But] I definitely didn't want to go into the City. It was based on personality - the few people I didn't like all wanted to be stockbrokers." At Cadbury's he was put straight on the road as a sales rep. "I thought that with a car and selling chocolate I would be irresistible to women, but then I was told to go and work for their Jeyes toilet cleaner division. I spent the first year and a half flogging toilet cleaner," he says.
"Being a sales rep is a great experience in itself, very humbling. You learn a lot about your persuasion skills and working with other people. You learn to read a map upside down and to read upside down generally because the buyer is always sitting opposite you."
It was as a "young and hungry" assistant brand manager that Glenn had his "first major disaster", promoting Cadbury's drinking chocolate. "The advertising idea - probably illegal today - was to suggest that Cadbury's drinking chocolate was the same as drinking a liquid version of Cadbury's Dairy Milk. The idea was that a cup would morph into a segment of chocolate. It was great, if not exactly true," he recalls.
"We did a promotion where you could send in for mugs. I massively underestimated the demand and spent three months in Stoke trying to get any pottery manufacturer to take up the slack and manage hordes of irate people who had dutifully collected their four lids to get their free mug."
He survived that error and was then made brand manager of Kia-Ora, which under his supervision rose from Britain's fourth favourite squash to number two in the market.
Having marketed drinking chocolate and orange squash, Glenn was tempted to the Square Mile, which he had shunned on leaving university, to become a management consultant for Deloitte. "I was lured a little bit by money," he says, of his three years in the City. "But I didn't want to be a consultant all my life."
Having snubbed the City once for an unglamorous job as a toilet cleaner salesman, he departed again, this time to market cat food. Most of his friends, he admits, "laughed" at the job change. At Mars Pedigree pet foods he was made marketing manager of the company's cat food brands, most notably Whiskas. The company sent him to work in Germany - "a very alien environment" - where he was given the job of persuading East German cat-owners to stop feeding scraps to their moggies and to give them Whiskas instead. His achievements were sufficiently impressive for PepsiCo to headhunt him in 1992 as one of a series of British managers picked by the American company after its purchase of both the Walkers and Smith's crisps brands. "I very quickly realised that the smart thing to do with those businesses was to merge them," he says.
One of his most challenging tasks has been to market tortilla chips to a previously reluctant British public. The market was then dominated by Phileas Fogg but Glenn went for the masses with the £20m launch of Doritos. He now plans to do the same with smoothies, taking on the Innocent brand, which is one of Britain's fastest-growing companies. Glenn acquired the PJ's smoothies brand last January and notes that it was "the pioneer" of such drinks, until it "got overtaken by Innocent".
He says: "Our mission is to mass market. Our belief on smoothies is that they are being positioned as too elitist and too smug. What they are is a brilliant injection of fruit goodness."
Some may not like the idea of a progressive British brand being worked over by a former British brand that now forms part of a giant American conglomerate, but Glenn feels that global businesses are sometimes unfairly maligned. "There's a certain section of the population for whom anything that is global is by definition bad. That puts a certain taint on the whole debate about healthy eating," he says.
Glenn's The Best Job in the World will contribute to that debate, but it will also serve as a handbook for PepsiCo staff. "I will make no money out of this," he says. "But this is a really good record of the growth of the business."
Later that day he is off to Majorca for a family holiday. He anticipates a home from home. "I know all the bars there will be showing Sky Sports, selling Stella ... and Walkers crisps," he says.
ON HEALTH PRESSURES
We are subjected to media and government interest in our diet. That's a good thing
ON WORKING AS A SALES REP
It's a great experience in itself, very humbling. You learn a lot about people
ON MARKETING SMOOTHIES
Our mission is to mass market. They are seen as too elitist and too smug
For more information about 'The Best Job in the World', see www.shoulders-of-giants.co.uk/Reuse content