Ford did b) when it replaced the square-cut Cortina with the jelly-mould Sierra, and sales wobbled mightily to begin with. Strategy a) came back into play with the massively mediocre 1990 Escort, a car which became half-decent only in 1995, after a mechanical and front-end visual makeover. But that makeover, with its simple, pointed-end-elliptical front air intake and its crisply defined feature lines, was to prove highly significant, for it was the new face of Ford.
We saw it next with the crisp-edge, smooth-curve theme in the little Ford Ka. Slow to catch on, the Ka now sells voluminously. Then we saw it in the Puma and - in extreme form - in the Cougar, both sporty coupes. Public softening-up exercise completed, this design language (Ford calls it Edge Design) now gives us the replacement for the ultra-mainstream, big-selling Escort. In conformity with strategy b), the new car has a new name: Focus. And, by any standards, it is an extraordinary-looking thing.
That's the idea, of course. Ford doesn't want anyone to confuse the Focus with its rivals (Golf, Astra and so on), so it must be instantly recognisable as a Ford. It is; but because it looks an evolutionary member of the new- look Ford family, instead of coming out of the blue as the Sierra did, the hope is that buyers will warm to its forward-looking futuristic aura rather than be frightened away.
Huge wheel-arch bulges, acute angles and minimum clutter are the themes. The Focus is not beautiful, but you can't help staring at its high-sided, slope-tailed form. The interior is a similar mix of curvy lines and triangles, and the instrument panel looks as though it has grown through the fascia skin, causing that skin to split like a pistachio shell and reveal the contents.
And so to practical matters. The Focus is more spacious than the Escort in every direction, and you sit commandingly high, although not high enough easily to judge the accuracy of reverse-parking manoeuvres past that tall tail. Visually intriguing as the interior is, it's not constructed from the quality of materials that makes a Golf feel special. To drive, though, the Focus is a delight.
The most popular engine is likely to be the new 1.6-litre Zetec SE unit, although you can also have a 1.4-litre version of the same basic engine, 1.8- and 2.0-litre versions of the engine family used in the Mondeo, or a 1.8-litre turbo-diesel. This 1.6-litre delivers 100bhp and a hefty dose of pulling ability, and propels the Focus with easy, refined vigour right across its speed range.
This is a very smooth engine, mated to a gearbox whose shift action is nearly as light, precise and oily as that paragon of a gearbox found in the Mark One Escort of 30 years ago. Why shouldn't it be? Well, in a modern, front-wheel-drive car the linkage between lever and gearbox is much more tortuous, so a sweet shift is harder to achieve. This engine is particularly impressive when trickling through traffic, too, thanks to clever electronics which banish any snatches and jerks the instant they threaten to happen.
Part of the reason for the Focus's vigour is relatively short-legged gearing, so the engine is spinning quite fast for a given road speed. This might sound like a recipe for poor economy, but not so; Ford's research showed that drivers press the accelerator harder in longer-legged cars, searching in vain for more pace and burning up more fuel. If the car is responsive, you press the accelerator only as far as you need to, and end up using "less" fuel. On average, a Focus 1.6 will go six miles further on a gallon of petrol than an Escort 1.6.
Sophisticated new rear suspension, zappily titled "control blade", helps towards wonderfully friendly, fluid and precise handling, and the steering is highly accurate without feeling edgy or nervous. Crisp handling usually dashes any chances of a smooth ride, but the Focus scores here, too. It's fun to drive, yet comfortable for passengers; dynamically it's the best Ford there has yet been, and they're all rather good these days.
The Focus went on sale two days ago, and comes in three- and five-door versions with a choice of four trim levels.
All have a minimum of power steering, electric front windows and two airbags. A four-door saloon and an estate car follow soon, sporty versions (including a possible Focus Cosworth) arrive next year. Our biggest-selling car-maker has just created the most striking-looking and best-driving car in the class, with an unmatched blend of attributes. Rival makers now have to match that blend. And that's good news for all of us.
Ford Focus 1.6 Zetec 5dr
Price: pounds 13,350.
Engine: 1,596cc, four cylinders, 16 valves, 100bhp at 6,000rpm
Transmission: five-speed gearbox, front-wheel drive.
Performance: 114mph, 0-60 in 10.9 seconds, 36-41mpg.
Fiat Brava 1.6 SX: pounds 12,585. Good-looking car with neat triple-deck rear lights.
Peugeot 306 1.6 LX: pounds 13,445. Getting on a bit, but still smart.
Renault Megane 1.6 RT: pounds 12,970. Part of Europe's best-selling car range. Fun to drive.
Volkswagen Golf 1.6S: pounds 14,495. Best built and best finished of all. Tyres squeal embarrassingly easily.