1) It does that just to make it seem a lot harder. Which is good. You can't do anything about that I believe. 2) Vehicles can't pull over as they are set on a path. Making them pull over would make them pull over would set them off their path they have to follow. However, it is possible. The only major problem would be that they would pull over into objects. I.E. Parked Cars, fire hydrants, lights, post boxes. etc. Then we have to shoot them, extinguish them, then carry them away. That would be annoying.