Fred; Your dampers cant absorb the undulations in the road surface that the stiffer and shorter spring exagerates. Thats the trouble with these lowering springs, any kind of rough surface and it knocks your teeth out.
Captain; Im not sure that keeping the footprint on the road surface (gravel, tar,snow etc) is a simple part of the suspension set up, matching dampers to springs, roll bars and chassis can get the better of oh so many engineers...
I wouldnt give up my Proflex for anything. Imagine running tarmac damper inserts on gravel/loose surface. you would smash the car to pieces with the forces transmitted through the strutt as the dampers are too stiff.
Dont really know where im going with this, just commenting on experience!