Whilst we wait for Mr Ballard to comment- my tuppence worth....
Dampers not only control the spring, but the body as well, certainly the damper rate- being velocity dependent as opposed to distance, has a huge effect on ride quality.
A too stiff damper, will make a car feel "jiggly" over small road surface irregularities, and larger irregularities will cause the ride quality to be skippy or crashy, because the damper will "prop" the car up rather than allowing the spring to soak up the bump
In my head a Morgan rear damper needs to be "relatively" soft in bump, but with more rebound rate, to control the huge unsprung mass of the axle (about 55 kg before you add in wheels, tyres and brakes).
Happy for Peter B's comments though, I'm good at getting Morgan's to handle on the race track- the road is an entirely different kettle of pilchards
