So my impression, the thought of a steering wheel spinning out of our hands is a manual steering problem. Yes, your old tractors (I drove one too) and the old manual steer busses. Yes, I've driven those too. I can't comprehend my power steering wheel pulling away from me, certainly not to the point of hurting my wrist.
If that were true, a blown tire would send the bus sideways across the median, flipping to its side and taking many innocent motorists with it. Ya, we've all seen the YouTube video, but I can't imagine that's a real daily risk we take.
A power steering system, like Scott has.. like I have, is easy to control, even in a rut, curb, blown tire, etc. A spinner knob on the steering wheel isn't going to smash my wrist. To the contrary, if the wheel wasn't firmly held, the spinner knob might be an asset by being easily "caught" by a unsuspected spin of the wheel. A quick correction of the wheel, by way of power steering, and the potential accident avoided.
Am I out to lunch?