BMW 730d

Designers and engineers may inhabit the same world but they seldom see eye to eye.

Those who pen the cars, for instance, are often branded fanciful and unrealistic while the mechanical types rub their corporate chins, suck air through their collective dentures and shake their heads dismissively.

A prime example of this of course is the concept car. Those that dazzle on revolving pedestals at automotive shows around the world in tarted up clay, wood and plastic bear little resemblance to the actual models that drive off the production line.

They are either impossible to manufacture at a realistic price, breach Euro health and safety laws - or in most extreme cases human rights - or would scare most conservative buyers silly.

In the end what we drive are the results of some sort of compromise and sometimes innovative technical skills so the designs actually work.

Take the 7-Series BMW as a prime example. This car inhabits CEO-land; it's a boss-mobile. It's not for the great unwashed; it's for those who not only want a decent way to travel but also a symbol of status and wealth.

Give that brief to a designer and the first thing he will draw is a bonnet the length of an oil tanker. And sure enough that’s what you get with the 730d and it’s all the better for it. That's 1-0 to the design boys then.

Thing is the engineers might just enjoy pointing out one simple fact; when your nose is that long it is going to get cut off by passing traffic every time you edge out of a side road.

No matter how far you crane your neck at the junction you can’t help being in the middle of the road by the time you can actually see - just leaving enough time to utter a short prayer before the juggernaut hits you.

It was going to be a long and dangerous week then, until that is, a small button on the transmission tunnel sporting a movie camera graphic was observed and depressed.

At rest, at the killer junction, the dashboard display that had been showing me the satnav map suddenly became a split screen television showing what was coming from the left and right - genius. That's an equaliser to the spannermen then.

The rest of the 730d shows a similar symbiosis of design flair and engineering prowess. Glance at the wing mirrors for instance and when there’s a car hidden in your motorway blindspot that’s picked up by their built in radar, a little warning triangle illuminates to tell you.

Under the long bonnet lies a 3.0 litre six cylinder diesel. You have to have one of those because they are the most functional offering good miles per gallon and efficiency, say the engineers.

Fair enough but for the designers it has to sound and feel right, offer breath-taking performance and be entertaining to drive, which of course it is.

But so often compromises please no-one and with the ride that could be true. Limos like the 7-Series should have a cosseting floaty ride which soaks up the bumps and comforts the occupants.

The problem with that is for the enthusiast it is like driving while under anaesthetic. It's all too woolly and numb to know where your wheels are and what they are doing. BMW don't do that sort of vehicle and sure enough the ride errs on the side of firm so the driver gets the feedback.

There's another natty little button on the transmission tunnel this time altering the suspension from comfort to normal and sport. They are all quite hard but it’s the way the lumps and bumps of the road transmit through the steering that is surprising. Now that’s a bit of a own goal to designers and engineers. It's not bad but it is noticeable.

At the end of the day the new 7-Series BMW was probably produced in the right spirit benefiting the most from a lack of compromise in design and engineering.

Car facts

Model: BMW 730d

Engine: 3.0 litre, 24v, six cylinder turbo diesel

Drivetrain: six speed automatic

Power: 245bhp

Top speed: 153mph

0-62mph: 7.2secs

Insurance group: 19

Miles per gallon (combined): 39.2

CO2 (g/km): 192

Price: £53,730.00