FWIW - Michelin City Grips have another indicator labeled "Rotation -->" marked periodically around the tire, on the tread surface, right at the junction of the sidewall and the tread surface. You have to look very closely to see it. Oddly enough, it points in the same direction as the arrow you picture on the sidewall. I never noticed the sidewall marker on the front tire but I have noticed it on the rear. Happily the rear tire rotation indicator, sidewall arrow and tire position all point towards/indicate directions that make sense.
Ridin' the IceBurg - 10% transportation, 90% fun!
90K and counting.