Chuck etal.
The primary multiple examples shown in the study were of the Nuovo Record rear derailleur. Cast in alloy, long tool life in comparison to a steel or bronze part where tool wear is much faster, hand working of the tool during its life was common and necessary. Don't forget the variations that would happen due to secondary processes, handling, deburring, polishing and plating.
If one was to study Gran Sport background textures, well I would expect them to have evolved all over the place.
I bet the steel and bronze parts were bulk packed until final assembly, the Alloy parts probably got more careful handling in the later stages of manufacture. The Nuovo Record components were in relation to the world market in the 6 or low 7 figures annually at the peak. No wonder there is such a steady supply that turn up on ebay.
Just wish they had run the machines more at the gum hood supplier.
John Jorgensen Palos Verdes Ca
Chasing raccoons away from my roof.