MPH: Mark Hughes on...

Active rear wings, set for introduction in 2011, will radically change the racing. This will be of a very different order to the last Overtaking Working Group measures that made only a small initial difference that was then wiped away with car development. A rear wing with an opening slot gap that dumps all the downforce and drag at the press of a button will make overtaking far easier.

When the brakes are applied, the slot gap closes again and reverts back to its standard high-downforce setting. Only the driver behind gets to use it, with dashboard electronics informing him when the device is armed. It leaves the guy in front defenceless, thereby almost guaranteeing lots of passing. But be careful what we wish for. It's already being compared to a losing football team getting a penalty - with the goalie not allowed to save it.

The FIA has reserved the right to tweak the system, with the teams that proposed it in the first place accepting it could be abandoned if it proves unsatisfactory. But it demonstrates a real willingness to attend to the problem. In a way it's unfortunate that it came in the wake of the Montreal race where the message was that F1's overtaking conundrum could be solved by deliberately mis-matching the tyre to the track.

It's actually probably a bogus claim. To understand why requires a bit of knowledge of how a tyre generates grip. There are two basic mechanisms - termed mechanical and chemical - that work in unison. Mechanical grip is that derived from the tyre's structure and the way it bends under load and resists that load by always trying to bend back to its static shape. In this way it 'grabs' hold of the track. As this bending process happens so it heats the carcass of the tyre.

Once it reaches a certain critical temperature, the surface of the rubber begins to interact on a molecular level with the surface of the track. This is chemical grip, whereby the tyre sticks to the track. The more it sticks, the more it can grab. Similarly the temperature increase caused by the grabbing enhances the stickiness of the tyre and a point of equilibrium is reached whereby each process is supporting the other.

That's the basic idea, but it helps to understand why a repeat of Montreal everywhere isn't feasible.

What was happening there was that the track's surface - particularly the patched sections that had broken up in 2007 and '08 - was of a very finely-textured asphalt and neither the super-soft nor medium Bridgestone could adequately 'grab' it. It had been made this way precisely so the tyres did not churn it up.

So there was very little bending of the tyres going on and therefore no heating up of the tyre's carcass.

Consequently the threshold temperature of chemical grip wasn't being reached. So with the below-temperature rubber hard and brittle, it simply sheared off as it was dragged across the surface. The problem was serious with both types of tyre but more so with the super-soft because its rubber was more delicate.

But the delta of difference between the patterns of the two tyres varied according to track temperature and how much the track had rubbered-in. Heavy rain on Friday night had washed the track clean and so the process had to begin all over again on Saturday. Only once the race had been underway for about 10 laps did the surface then start offering enough grip for the tyres to begin grabbing the track, thereby warming and triggering chemical grip.

Valencia's conventional track surface meant the tyres behaved perfectly. If we want races to be more like Montreal - with teams having to make on-the-hoof calls based on insufficient data - the key would seem to be the track's surface, not that of the tyre. What about surfacing them all with low-grip, finely-textured asphalt and ideally sprinkling them clean after each day's running, too?