The description is accurate if hardly adequate. In fact, Mr FitzWilliam- Lay is president of a courier business that was recently listed as one of America's fastest-growing private companies by Inc Magazine. Called Citipost, it will soon be in 16 US cities and recently opened shop in London.
Citipost is run jointly out of a modest West Manhattan warehouse by Mr FitzWilliam-Lay and his partner and the company's chief executive officer and founder, Richard Trayford, another Brit. Launched in 1991 with an investment of $19,500, its revenue this year should exceed $18m - that represents growth over five years of 1,664 per cent.
This being New York, however, Citipost's journey has not been without bumps. There was the embarrassment of one of their employees being nabbed two years ago as the mastermind of a $1.9m Tiffany's diamond heist. Much more awkward, however, have been their brushes with the Manhattan Mafia.
They make an intriguing pair. "Ex-greasy rocker meets Toff," suggests Mr Trayford, 33, who, after being expelled from Devizes Comprehensive, was a bass guitarist with aspirations to rock'n roll fame before stumbling into the delivery industry after a spell as a motorcycle courier in London.
Mr FitzWilliam-Lay, 31, by contrast, studied computer sciences at Edinburgh University and came to New York, via a brief modelling stint in Japan, to help the Economist magazine computerise its accounts in America. Before meeting Richard, he worked as a chef in the trendy mid-town restaurant Vong.
Their secret: offering an overnight, proof-of-delivery, mailing service for volume mail that is exempt from the statutes that give monopolies for ordinary letter carriage to government postal services like the US Mail and, in Britain, the Royal Mail. In practice, this means a lot of printed material from financial institutions as well as media and entertainment companies.
The principle distinction of Citipost, however, is its low-low prices. Rather than attempting to deliver everywhere, like the US Mail or the mega-courier companies like Federal Express, Citipost operates exclusively between cities and between business districts within those cities. "We don't do the farms or the suburbs," Mr FitzWilliam-Lay explains.
Nor does Citipost have huge fleets of lorries and aircraft. Parked against the wall of their Manhattan warehouse are rows of tri-carts - small metal trollies that Citipost employees haul around the sidewalks of Manhattan. For inter-city and international carriage commercial airlines do the work.
The strategy now is breakneck growth. By reaching abroad - aside from London, Citipost is in Frankfurt and will soon be in Hong Kong - the company hopes to tap into the flood of exempt mail coming into America. Incredibly, 17 per cent of all business-to-business mail entering the US from abroad is bound for addresses on Manhattan Island. New clients even include some monopoly state mail services, including those of Denmark and Switzerland.
"We intend to spread all over Europe and to key points in Asia," says Mr Trayford. "Once you decide to keep growing you cannot just stop. Hopefully we will become big enough that the reward will be at the end of the rainbow." The implied treasure will be the proceeds of eventually going public.
The two Brits laugh now about the diamond heist. It was perpetrated by one of their couriers who happened to have the flagship Tiffany's store on Fifth Avenue on his daily route. In the two weeks before the police finally caught up with him, he continued making his daily calls at the shop.
On their tangles with the Mafia, they are, not surprisingly, more circumspect. They suspect, however, that their main competition in New York, three other exempt-mail courier companies, are all fronts for the feared Lucchese organised crime family.
But while they have been intimidated verbally, no physical harm has come either to themselves or the business.
"The only reason they ignore us is that with their courier companies they want to maintain a public appearance of propriety and they have to turn over their cash," Mr Trayford ventures. "The atmosphere in the industry, though, is that there is absolute corruption going on."