However, if the tyres are developed properly though (which is where I'm questioning Pirelli's competence), this dependency should be minimised (for obvious safety reasons) and there should be enough margin in the durability of the tyre to allow the degradation targets to be reached without the tyre destroying itself under normal operating conditions. Furthermore - curbs, debris and car to car contact are normal operating conditions and have been for over 100 years of racing.
Pirelli rely heavily on the ignorance of the public when they throw their smoke grenades after a failure - with their classic one being the deliberate confusion of degradation (which is related to the tread compound) with durability (which is related to the carcass design). Keep the following definitions in mind the next time Paul opens his mouth:
- Degredation is a chemical change in the tread rubber whereby the coefficient of friction drops off after a certain time (mainly dependent on its thermal history). This can happen with 90% tread remaining or with 10% tread remaining - therefore its not something that causes a change to the shape of the tread or carcass. It may show some correlation with wear but it is NOT wear.
- Wear Is the tread rubber physically coming off the tyre due to the shear forces in the contact patch. This is obviously changing the structure of the tread and as can be seen on road cars, its possible to wear it off completely and you are left running on the carcass which is obviously not good. The tread is not structural but the carcass is - so if the tyre is developed properly, it should degrade before it wears out. Which is why I call BS on their claim that Vettel's tyre explosion in Spa was due to wear. It shouldn't be possible if the tyre was designed properly in the first place.
- Durability is the ability of the carcass to survive normal operating conditions which includes downforce, lateral and longitudinal cornering forces, lateral and vertical impact forces as well as car to car contact and debris. This is largely dependent on the carcass design - i.e. type of material of reinforcing plies, ply orientation, number of layers. This is the stuff which takes all the cornering and braking loads and should be relatively independent of the type of tread which they lay over the top.
This is why I have a low opinion of their F1 activities. Not only are there durability problems with the tyres, but the fact that they try to attribute this to the requests for wear and degradation I find to be extremely dishonest.