No, the theory is that the power steering system is part of the oscillation known as death wobble. If you drive the steering gear backwards (from the pitman), the inertia of the steering column and steering wheel might be enough to twist the torsion bar a little bit. For example, if your wheels get kicked to the right by a pothole, this could be equivalent in the valve to a steering input to the left. As the system starts to go left, it could sense steering input to the right and so on, back and forth. If you take off the power steering belt, there is no hydraulic assist, so that part is taken out of the picture.
