This was bugging me! So I went on a google mission, and found the answer, I think!
See info below from various sources, mainly continental home page...
The forerunner to the new ContiSportContact™ 2 was ContiSportContact performance patterned tyre. ContiSportContact is slowly being phased out but until the new sport pattern is manufactured in all the sizes this tyre is OEM replacement on most European cars.
Features of the ContiSportContact
• Improved wet traction with open inner shoulder
• Precise cornering stability and good steering precision
• Minimal rolling noise
• Available in Y, W and Z speed ratings
• OE on Europes finest sports cars, including the Porsche 911
Made for high-performance, this tyre has asymmetrical tread design and precise response which is why it was approved as original equipment on the Porsche 911.
Asymetrical tread pattern:
The distinct and asymmetrical tread pattern (1) has more rubber in the compact outer shoulder than in the inner shoulder. This extra rubber in the outer shoulder enables the tyre to have a larger contact area with the road. Your profit: Thanks to the asymmetric tread pattern with compact outer shoulder, cornering stability is increased, and a precise steering response of the tyre is ensured.
And spec of a simialr tyre...
The Conti Winter Contact TS 790 has an assymetrical, but not directional tread pattern.
For this reason the TS790 must be fitted with the sidewall lettering OUTSIDE facing outwards in order that the tyres performance is optimized.
When the tyre is fitted on the rim in this way, then it is the right way round and can be placed in any wheel position on the car.
ContiWinterContact TS 790 tyres fitted in accordance with the manufacturer´s recommendation
In order to optimize the traction properties of the tyre, the sipes in the tread pattern blocks are not positioned laterally, but angled. In the central ribs of he tread pattern, the sipes are angled in such a way that they oppose one another. This arrangement is designed to provide excellent high speed driving stability.
The fact that the tread pattern grooves are pointing forwards on one side of the car and backwards on the other side, does not in any way affect the overall performance of the tyre on wet or dry roads.
If the tyre is not mounted in accordance with the manufacturers recommendations, then the special performance advantages of the assymetric tread pattern are not realised.
The assymetric tread pattern of the Conti Winter Contact TS790 is designed to cope with the different demands placed on the outer and inner shoulders. The outer shoulder tread pattern is more closed to provide outstanding driving stability in curves and excellent steering precision. The comparably high number of tread blocks in the inner shoulder guarantees the highest level of traction in snow due to the biting effect of the block edges.
The Conti Winter Contact TS 790 combines, not only because of its tread pattern, top class winter performance, a high level of safety and a striking appearance.
RESULT! STILL SEEMS DAFT TO ME THOUGH!
