I had to drive in convoy through central London last week behind the Top Gear producer in a bright yellow Porsche Coxster. Or Gayman, to give it its official name. You might imagine this would be quite a thrill; driving through one of the most vibrant and amazing cities in the world in an egg yellow Porsche. And indeed you’d be right. It was quite a thrill. But only for me, in the car behind.

Very often in car magazines reporters will claim the car they’ve been driving caused a bit of a stir as they motored along, but this is only to make the job of road testing seem more important than is actually the case. It’s almost a cry for help. “Hey, I’m not a nerd. Everyone loves cars.”

But the fact is that here in Britain you could drive a polka-dot Rolls-Royce through the Queen’s legs and no one would look up.

One bloke in Autocar claimed recently that a Lamborghini Gallardo caused “absolute mayhem” when he parked it in a Tesco car park. But I assure you it didn’t. You get “absolute mayhem” when you drop a cluster bomb in the residential area of a big city. What you get when you drive a Lamborghini into a British supermarket car park is called “studied indifference”.

However, if you have a yellow Porsche Coxster it turns out that people will turn round and point. And then they’ll nudge their friend, who’ll point too. And then they’ll both have a jolly good laugh. Twice people leant out of their vans to call my producer friend a student of onanism.

And then there’s the reaction he got from people in proper Porsches, by which I mean the 911. They laughed, too. Because turning up in the big city in a Coxster is like turning up to Elton and David’s white tie and tiara party in a rented DJ.

Of course, from behind the wheel you are blissfully unaware of the hysteria in your wake. Because of the limited rear visibility you simply can’t tell that you’ve turned London into a scene from a Smash commercial. You’re sitting there thinking, I look good. I feel sharp. I’ve spent £43,930 on a mid-engined sports coupé. What a tool . . . . . . you look.

What you’re doing is strutting through town with your flies undone. You’re commuting to work with your skirt tucked into your knickers. The Coxster? It’s like congratulating someone on the forthcoming arrival of their baby only to find they’re just fat.

The poor think you’re a git for having a Porsche. The people with proper Porsches think you’re a git because you actually don’t have a Porsche at all. The Coxster, then, is the most embarrassing car in the world, except for one thing . . . it’s beaten, just, by the car you see in the photographs this morning. The Nissan Micra C+C.

I honestly don’t know where to start with this one. So let’s begin at the meeting where I presume someone decided that what the world needed most of all was a Nissan Micra with a heavy and complicated folding metal roof.

Now we all know that meetings don’t work.

All of them — with no exceptions — are a complete and utter waste of everyone’s time. Show me someone who goes to a lot of meetings and I’ll show you someone who doesn’t have a proper job.

All the great inventions and great leadership choices come from the mind of one egomaniac who then gets the job done. Everything after the initial idea is formulated can be achieved by e-mail.

Meetings are where good ideas get watered down and bad ideas are forced along because no one ever has the courage to stand up and say: “What the bloody hell are we doing here?” You may have seen an item on Top Gear recently where the three presenters were roadies for the Who. At the editorial meeting that sounded brilliant. “Imagine. We all get lost. Our vans break down. And the band have to go on stage the next night and do an acoustic set because we broke their amps. Ha, ha, ha.”

Of course, someone pointed out that we couldn’t actually do any of that because 80,000 people had bought tickets and the Who weren’t going to let them down just because three apes from a pokey motoring show on BBC2 wanted a laugh. So obviously we couldn’t get lost. And we couldn’t break their equipment and we couldn’t break down either.

Collective thinking, however, decided that it was still a great idea. And so it went on television. And it wasn’t.

I suspect this is what may have happened with the Micra C+C. At some point there must have been a meeting where someone explained that the cost of the motors needed to power a folding metal roof had fallen in recent years. And that as a result it would make economic sense to fit such a thing to even the smallest car. Yes, even the Micra.

Wow! Imagine that. Our fun’n’cheeky bite-sized’n’cute little shopping car could have the security of a metal roof when it’s raining and then on sunny days the roof could glide electrically into the boot. Brilliant! However, I refuse to believe it took very long for the big flaw in the plan to rear its head: specifically, the roof wasn’t actually going to fit in the boot.

Instead of canning the project, though, they made the separation point between roof and windscreen much further back than is either ideal or aesthetically satisfying. And obviously this still wasn’t enough so they had to enlarge the boot by fitting what can only be described as an aircraft hangar on the back.

The result is one of the ugliest cars ever made. I’m no fan of the normal Micra but at least it is sort of sweet. The C+C isn’t. It is enough to make your dog sick.

And to make matters worse, because they’ve located the separation point so far back, smaller drivers, who sit near the wheel, are still effectively under cover even when the roof is down. Oh and the rear seats are big enough only for transporting amoebas.

So yes, Nissan has indeed ended up with a convertible hatchback. But the cost of fitting a folding metal roof has rendered the car utterly useless. It’s ugly, impractical and, at £15,250 for the top model, bleeding expensive.

It gets worse. Because of the motors needed to make the roof work, and because of the strengthening beams fitted to compensate for the loss in structural rigidity, the C+C is about two million tons heavier than the standard car, which has an effect on both performance and fuel economy. Oh, and it’s a price not worth paying either because despite the strengthening beams it still has the worst scuttle shake since the old Ford Escort XR3i soft top.

To sum up, then, it’s ugly, impractical, very expensive, slow, not terribly economical and unpleasant to drive. The only good thing is that it’s made in Britain. But so is the Mini Convertible, and that’s much better.

The worst thing about this car, however, is the deep, stomach-churning embarrassment of being seen in it. I’m used to being pointed at and abused when out and about but I’d say the Nissan caused the insults to double in number. And because there was no roof, I saw and heard them all.

One sunny Sunday I had to plan a very special route to a friend’s house for lunch. I wasn’t interested in getting there quickly, or safely, only in not driving through any built-up areas.

Someone, at some point in this car’s development should have had the courage to pull the plug. Unless of course I’m wrong and the plan wasn’t to build a convertible hatchback at all. Maybe they sat down in Japan and said: “Hey, guys. I hear Porsche are doing a yerrow Coxster. It’s supposed to be the most embarrassing car in the world. Do you think we could beat it?” They have.

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