On Tuesday, April 6, 2021 at 10:54:41 AM UTC-7, Axel Reichert wrote:
Frank Krygowski writes:

Schwalbe says that for road tires, it's essentially cosmetic.
To my knowledge, any tread on road bike tires is called "marketing
tread" by Conti engineers.

I am not sure, though, whether the internal layup of the various plies
might be asymmetric. But I would be surprised if this were the case.

Axel

What I find odd is that most of the tire will be worn as thin as a piece of cheap toilet paper and yet those markings, I hesitate to call them grooves, are still showing.