Yup
A road grader has the blade between the wheels for a reason. With a box blade hanging out there by itself with a slight lift to alow material to be deposited evenly, when the front wheels go into a pothole, the box lifts and leaves a high spot. When the front wheels go over a rise, the box tends to dig in. With gauge wheels, you can let the 3PH set down in the float position with the toplink disconnected. In this configuration, the gauge wheels set the height for even dispersal and the whole affair is less effected by the tractor rolling over road countours. It will cut into the high spots and deposit more material in the low spots. That is the advantage of the "Duragrader" type designs as they set down solid on the ground while their blades cut a small ammount of material that builds up and flows evenly over the top of the low blades. they cut harder in the high spots and material goes under the blades when passing over the potholes. They do not appear to be really effected by tractor movement.
I am in the process of building my own modeled after the "Big Boy" shown in the Box Blade Photo comparison post(around page 11?). It has a swing down gate in the back to hold in material to allow it to be drug into a pile and/or relocated to another location. I only really need one for driveway maint. If I had need to relocate a lot of material, I would want scarifier teeth to break up and collect more material faster as the low fixed blades only take a small cut.