No apology necessary Norb, its good to know some bugger that knows his way about the innards can put any reports from a second rate steering wheel attendant into some mechanical context.
I wasn’t blaming ZF at all for the clutch failings, its not the first bloody clutch thats like an on/off switch 
, i started out with an old S39 Foden in the dim and distant past, which had IIRC sintered iron pads as the clutch facing material, if you tried to slip these buggers the resulting judder would shake you fillings out and with the cast steel steering column bolted directly to the chassis 
well you can well imagine the shocks that travelled up said column…and i wonder why everything bloody aches now, in fact its a short list of bits of me that don’t hurt 
I blame the MAN workshops for not taking notice of my report of excessive judder seriously, if they had investigated at the inspection when i mentioned it the clutch could have been replaced when convenient without a tow in and unplanned downtime three months later.