Last week I speculated that McLaren would unveil the successor to the F1 at the Paris Motorshow so, of course, no sooner were the words up on the website than McLaren made them instantly redundant by showing a picture of the car, to be called P1.

Although McLaren has not said as much, it is now clear the car will have a carbon body, an adapted version of the MP4-12C’s carbon tub and some form of hybrid drive to boost the output of its twin turbo engine. So at least I got that bit right.

As for its potential, McLaren makes a point of saying its goal is not to go chasing top speed records but, instead ‘to be the quickest and most rewarding series production road car on a circuit’. This is of course a highly commendable approach, though whether it also proves highly commercial is another matter. A car’s top speed is a pretty irrelevant item of data for most machines, but none more so than hyper cars like this and the Bugatti Veyron. But, and as Bugatti has ably demonstrated, it sells cars.

What interests me most about the P1 is that McLaren has decided to make it a hybrid, such as has Porsche with its forthcoming 918 Spyder, as will Ferrari with its replacement for the Enzo. The question is why?

What will a hybrid drive bring to such cars that would not have been achievable through conventional means?

First and foremost, it gets your attention. A 210mph Porsche with 580bhp capable of 94mpg is a dream for headline writers regardless of the fact that this says everything about the increasingly farcical way in which consumption figures are calculated and nothing whatever about how the car will behave in the real world.

Secondly it links the car to the world of racing. It is no surprise to me that the two F1 constructors who also make road going supercars are following Porsche – which will soon return to Le Mans with a hybrid racing car – down this road. Whatever systems are used they’re unlikely to be KERS for the road, but that will not stop people making the connection in just the same way they did with flappy paddle gearboxes or steering wheels pointlessly plastered with switches and controls.

Finally hybrid power offers the opportunity for owners to drive an impossibly powerful supercar with the added bonus of being able to project superficially plausible environmental awareness even if the slightest scrutiny will reveal it to be entirely spurious.

But there’s a large pachyderm sitting in the corner. The great unknown is what these hybrid systems will actually bring to the driving experience: in what ways will these cars be not merely more economical or faster or closely related to a racing car, but actually better to drive for their hybridisation?

My concern is that for all the additional power a hybrid system might bring, so too must it bring additional weight. And if we’ve learned anything since the dawn of the sporting car it is that if you want to make a car better to drive, reducing weight beats adding power every time.

Every so often a few motoring hack chums and I ponder afresh the identity of the greatest road car we have ever driven. And the conversation always ends with two camps split between the Ferrari F40 and McLaren F1, designs that went on sale respectively 24 and 18 years ago.

What did these supercars have that those of today lack? They were light, and almost impossibly so by today’s standards. When I doodle the specification of my optimal supercar on the back of a metaphorical fag packet I always arrive at a front-engined machine with a  carbon tub and body, powered by a normally aspirated engine of around 4-litres providing around 450-500bhp in a package weighing less than 1100kg. It would not aim to have the highest top speed like a Bugatti Veyron, nor set an unprecedented lap time like a McLaren P1. It would seek simply and solely to provide the richest driving experience known to man. Will hybrid help this happen? I look forward to finding out but, until then, I’ll have my doubts.