the seats are nearly on the back tires... this results in every slight movement of the rear end to seem exaggerated to the occupants... so what he felt is nothing odd just that it was the first time he felt it probably.

i find it to be a total kick when i go over a bump in the road at 80+ and the rear shifts a bit and your passenger freaks while you fully know there is no way in hell the 255 tires in the back are going to break traction when they hit the pavement again. :P