Similar to an ice road. They are too close together and travelling a little to fast. Those large amplitude waves get a lot smaller with a more evenly spread out displacement. You displace the equivalent weight of the vehicle in water. 1 cubic metre is 1000kg those cars are near 2000kg. If you space them out better the displacement is not so localized and the wave amplitude is much smaller. On an ice road it can be the difference between trouble and normal operation. Ice road, as in Northern Canada where there are no real roads, but access is required. Some areas are one lake after another. Manitoba alone has over 1 million lakes.

Mark