you get a lot more miles, most have a flatter contact patch on the road. reversing it put the carcus plies in the correct direction in order to make the tire stronger and not separate. When the tire is used on the rear most of forces on the tire are on acceleration and when it is on the front most of the forces come from braking.
Ah, it's a trike thing. I hadn't twigged to the three wheeled subject matter. I was thinking this might be a "Dark Side" thing.