Hi Peter
Thank you for your advice.
Now with 400 miles of motorway I am very happy with the performance, however I am unfortunately not qualified to describe the ride in technical terms.
Tyres are 21 all round.
The car originally did not have dampers and did not experience shimmy, however the installing garage insisted the blade dampers were refitted.

I am tempted to remove them, ah but probably won't.
Ball thrust bearings were fitted before suplex and remained.
The damper top stud nut as fitted by the installer is very tight, and compression of the rubber is apparent, movement of the top washer is not possible. I may in the fullness of time see what occurs when I release this a bit, as you suggest it may even out the jiggle.
The drifting of the front end I perceived may in fact be down to the worm and peg arrangement and is something else I know very little about.
I am a big fan of this system, the ride is still hard and I think I need to improve the tracking and balance for and aft in the suspension, but overall now at least I am happy to go touring with zero headaches per mile, and yep clocking up those smug smiles.

Rdgs Dave