DJ Taylor: The neutral observer might assume Darren is a management consultant - but the memo states he's an 'upshifting technocrat'

In his late twenties, shaven-headed, broad, bustling and with a voice that contrives to be both loud and whiny at the same time, Darren is one of those commuters who cause such irritation to their fellow-passengers on the early-evening trains out of London.

It is not just that he manages to cram at least three pieces of electronic equipment on to the table-top where he takes up residence; it is not just that his mobile ringtone (Kasabian at top volume) goes off like a miniature volcano at four-minute intervals; it is simply that he talks all the time, and that the talk, apart from occasional confidences about women with names like Joolz and Becka, is invariably about his job.

And what does Darren do every day at the medium-sized office block on Cheapside with its Brutalist architectural backdrops and tanks full of exotic fish? The neutral observer, catching the occasional remark blown back from a hinterland where finance meets technology, might assume that he was some kind of management consultant.

Alas, it is all a great deal more complicated than this. If pressed by friends – although Darren's acquaintance is of the kind that tends to take one's professional life for granted – he might concede that he is in the business of "identifying platforms" with a view to promoting "synergistic solutions". The print-outs next to his laptop bear such eye-catching slogans as "top-down difference/sameness co-efficient" or "infiltrate the blur".

What is the blur, and how exactly is Darren infiltrating it? There are times when Darren himself would be hard put to define his precise function, for this is a fast-moving world where a job description can reinvent itself almost from the moment it is written down and the jargon mutates from one positioning document to the next.

Three months ago he would probably have described himself as a "paradigm strategist". Six weeks back, he introduced himself to a meeting of communications analysts as a "process game-changer". Yesterday a memo came round headed "technocratic upshifting".

Whatever it is, it pays him £60,000 a year and subsidises a highly agreeable bachelor lifestyle down in Tenterden. The only dissatisfied party is his mother, a fond and respectful parent, deeply impressed by her son's career and his shiny suits, who would love to be able to brag about his achievements and expertise to her friends, if only she knew what they were.