Nick Mason: 'I wouldn't want to fly in a bi-plane 747. Would you?'

A sad fact of the motor industry is that, in the modern world, one disastrous car design can cost a company its independent existence. Given this, it is hardly surprising there is an increasing move to attempt to anticipate reaction from the great buying public by producing show cars. These now usually consist of a mass of technical and cosmetic ideas that may eventually appear on any number of a manufacturer's models.

Jaguar's recent unveiling of the RD-6 at the Frankfurt motor show, to much acclaim, is just such an example. It may be cruel to mention it, but the horror of the Jaguar XJ220, in the Eighties, must still haunt the Jaguar executives.

A fabulous-looking car sitting on a motor-show stand excited a host of buyers. This was followed by a bloodbath of cancelled orders and threatened litigation when the cars were ready to be delivered. And lest they ever forget, every so often one of these cars lurches on to a dealer's forecourt like Frankenstein's monster, but a lot more frightening, and less saleable.

I speak with authority on this, having waved a sad farewell to my deposit on an XJ220, rather than pay the rest of the money and take something that felt as big as a Zeppelin, had a weedy six-, rather than 12-, cylinder engine, and was made in sufficient quantity to ensure scarcity would not aid its value.

So given, as company sources say, that the Jaguar RD-6 is unlikely to appear in your local showroom, what good things might surface in future Jags? The RD-6 is a diesel, and diesel power is already appearing in production Jaguars. The good old days of the diesel as circus car with smoke and clanking are long gone. A six-cylinder V6 engine capable of 0-60mph in less than six seconds and a top speed of 150mph shows real commitment to the principle. With this sort of car I don't think cost is such a consideration as convenience. There is a tortoise and hare effect when a great drive through France seems to consist of a tour of the filling stations.

Thank God, the bulk of the retro look seems to have gone. I liked flared trousers and Beatle jackets at the time, and I still have a 3.8 MkiII Jaguar, but please make new cars (and new clothes) reflect the present day.

It is OK for a bit of fun, but automotive retro styling is like Boeing developing the biplane version of the 747. The good-looking RD-6 uses aluminium for the body, a trick Audi used on the A8 when it was introduced. This motoring equivalent of the Atkins diet gave instant sports-car performance to what could be a bit of a tank.

The doors are interesting, too, using a French window effect, with the rear door hinged at the back. Great for West End premieres and one reason the new Roller has them, I would imagine. They should also be popular with body shops since some will doubtless be lost to careless passengers and passing traffic.

If Jaguar can engineer all these good things into the next generation of cars we may well be grateful Ford bought the company rather than see it disappear forever.

The writer is a founding member of Pink Floyd and collects racing cars.