Get a few more miles out of the tires that way. I noticed that the Schwalbe Marathons are directional, but I don't know if reversing the tread would have any major effect. I did the swap on my Gatorskins and damn near wrecked trying to stop fast. Once they're worn now, I just replace them. But I've been able to extend the life on a many a set of Hutch's, Mich's and Conti race tires by swapping front to back and flipping the tire on the wheel.