MR AVERAGE, we are encouraged to believe, owns 1.5 silver Ford Focuses, has a tenner in his wallet, enjoys spag bol on Mondays and a fish supper every Friday.

He also has two minor domestics a week. Days not specified but probably over whose turn it is to drive half a car.

Tupperwear set membership has other essentials: get up at 6.57am, home from work 5.15pm, go to bed at 10-39pm after somehow squeezing in nine hours of television.

Try to spend £12 on drink every week, £76.02 on shopping, £15 on DVDs and have a couple of nights out each month with friends. A tall order because apparently only two of the neighbours are on speaking terms. Could it be the half a car is blighting the street?

Oh, and don't forget to exercise two and a half times a week. I don't think I have ever had half an exercise. A sort of perspirous interruptus. I think I would go for the second half, followed by the £12 drinks ration.

It's this kind of fractional dreariness which renders most writing on Ford's best seller pointless. Because the outstanding Focus feature is its handling and there seems little likelihood of someone who spends more on Harry Potter than dry white discovering it has the grip of a drowning man, while racing home to snub the neighbours

Clearly many people are willing to wear the cloak of social invisibility. Which you can do in a family hatchback but not driving an Infinity M30. Frankly you may as well combine espadrilles with football shorts and tattoo mum and dad on your knees. In orange.

People will stare, some because the M30 is hardly born of the ugly tribe but most because to many Infinity is still a novelty. A riddle, wrapped in a mystery, inside an enigma delivered by a black curtained, marque-badged wagon.

Some of the neighbours were convinced Sebastian Vettel was being dropped off. Or his spare Champagne.

The M30 is Infinity's executive saloon in the world of BMW 530s, Merc E350 and Jag XF. Today's sample is the diesel GT Premium which is more expensive than equivalents of the above so it's not price the luxury arm of Nissan is relying on at £46k.

It's about the engine then? No. You can hear the three-litre V6 turbocharged unit in traffic which may not be right at the price. Spank the pony though and after hitting 62mph in a reasonable but not exceptional 6.9 seconds, it cruises beyond 3,000rpm in peace, the sort of hush telling the couple at number 47 you are a journalist brings. Silent as a Wapping pub. And 38mpg isn't bad either.

So, must be sporting prowess. Hardly. The seven speed gearbox changes regally and while  pushing on is uneventful this is not a car that encourages unbridled lust.

What makes the M30d tick is refinement, with a long list of kit. It is well finished, mature analogue clock, crisp fascia layout and bondage amounts of leather. Decadent? Even the steering wheel is heated.

For fun we have touch screen navigation with voice recognition. It won't respond to shut up you nagging android, I tried.

Enjoy an Albert Hall sound system in the comfort of your own purified air while avoiding distressing hospital menus thanks to blind spot warning with intervention, bandits in the rear warning, forward proximity alarm, intelligent braking and lane departure alerts.

That's not everything, but you get the idea. And soon, for the pious, there will be a hybrid.

A Merc or BMW will certainly blend in more and Mr Average says he enjoys 80 per cent happiness and 70 per cent normality.

But it could be that driving the Infinity with make you abnormally very happy indeed.