GUYS, watch the video again.
You can clearly see the Semi Truck is like 90 percent on the left lane, which is the lane the LS460 is directly behind. The Taurus was in the right lane, watch the wheels of the semi in relation to the center line of the road. The Lexus is clearly getting the most of the rocks here.
They also chose silver for the Taurus which hides visual rock chips well, while white for the LS460 which shows rock chips much more pronounced thanks to the contrast with the layer darker layer underneath.
Those Dirty Dirty people at Ford.