My first thought or better my guess was as mentioned in the strings of your link it also to be a piece of craftmanship based upon the traditional system from journeyman to master / geselle - meister / compagnon - maitre .
Especially when I am looking at the quality of the pieces.
But as I can not back that up by whatever proof it remains an open question to me. So thank you for your reply, making two of us not knowing
Best regards
Gunar