Steering dampers, further thoughts
The Kaw damper has an initial "no damping" stroke, then it bites. (You need to spend a lot more than £40 to get "instant damping".) I've set (by accident) the radius of mine so that this undamped movement is big enough to obviate slow roll (so the normal minute corrections when running straight are undamped), but it bites as soon as a sudden movement is made.
If it is moved slowly enough, any damper, on any setting, offers little resistance. The metering device only kicks in if you try to move it fast. (There are oil drilling tools that work on the same principle, which is where my knowledge comes from.)
In my experience, tank-slappers start with a large, violent movement, and that first one is the one you have to stop. Hence my damper is set on max, but is unnoticeable in everyday use.
The identical one on my Petty Norton is at a much bigger radius, about 6 or 7" and even one click is noticeable at low speed. What that suggests to me is that the bigger the radius, the more sensitive the damping: there must be an optimum.
I'm by no means certain that I've got this right, although obviously the radius of action AND the stiffness of the damping must be significant, but the speed of movement is also important.