It can't be much fun working at the Driver and Vehicle Licensing Agency. Since

1988, when Paul Channon, then Transport Secretary, authorised personalised number plates on the basis that they would 'add to the enjoyment of the nation' and you became the marketing man responsible, you've helped to sell 260,000 'cherished number plates', as you call them, and made more than pounds 140m for the Treasury.

But have you really thought about what you're doing down there in Swansea? In particular, how do you justify your latest poster campaign celebrating Neanderthal driving instincts?

You'll recall that the poster shows a huge number plate 321 GO and encourages your potential customers to 'Get off to a good start' with a personalised plate. What sort of start is that, Mr Roberts? A wheel-spinning, flash-git, up-yours sort of start? A 321, let's pretend to be rallydrivers sort of start?

Did you, I wonder, discuss the possibility of conflicting messages with your colleagues at the Department of Transport, whose gory new posters about the penalties of speed could find their way on to hoardings next to your own? Do you intend to enclose a 321 GO leaflet with licences endorsed with offences when you return them to the owners? Have you heard about the EC recommendation that advertisements should avoid references to speed?

It's not just the posters. You are greasing the axles of the yob car culture. Your plates encourage the notion that we are what we drive, that we must bond with our vehicles. I don't deny that if Tom Nichols, the 'roly-poly car dealer from Bromsgrove' whose pounds 10,000 number plate reads FAT GIT, were to pass me on the motorway I'd give him a toot and have a laugh just like everyone else. But your smile must have frozen after four years of hauling in the money for cretinous monosyllables.

The final reward of your work is parked outside a thatched cottage in Waltham St Law-rence, where the twin Jaguars belonging to

Zed and Marianne Zervides sport the pounds 50,000 his 'n' hers plates A1 SLOB and A1 SLAG. How can you sleep at night? Don't you think you should make it clear that vanity plates are the motoring equivalent of a medallion and that wearing one you'll be Tarbucked with the same brush as ageing comics and owners of caravan parks? Speed cops and parking wardens will take delight in booking you.

I know that you are looking forward to the pre-August sales of M-reg plates, especially in Scotland where, as you rightly say, a lot of people are called Mac-something. Thank you for pointing out that M1 SUE could be mine for just pounds 6,000. If I have a total frontal lobotomy before the summer, I'll be in touch.

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