[Bicycle Bob]

I find thought experiments far cheaper, and well worth it to direct specific features. Four wheel steering is seldom worth doing. You usually just yaw the vehicle to steer the back - having them steer as well is pretty redundant most of the time. The Honda all-mechanical system was interesting. At first, the rear wheels steered in the same direction as the fronts, but less. This would let you do a lane change with less time forcing the car to yaw. Turning the steering farther sent the back wheels the other way, to achieve a tighter turning radius for parking.