What size of rock where you blowing?
I take care of my neighbors/good friends yard (3 acres), the road grader always blows tons of rock in the ditches every snow.
The rock goes about 10' back and her property runs for about 400 yards along the road. I also mow across the road in the other ditch so I half to clean out both of them , I try a rake but it never works to well, I end up on my hands and knees picking up rock for about a day.
The rock that ends up in the lawn range from 1 to 1 1/2", clear up to 2 1/2 to 3" I wouldn't hardly think that a leaf blower would have the power to blow them back to the road. Although I have a nice gas powered Echo leaf blower, I might try it and at least get the smaller ones out.
Thanks for the tip