Dear Philipp,
thanks for your once again excellent information.

If the only difference between the 1953-DSS and the 1960-DSS is the design of the glass, then the case of the 1953-DSS was already able to withstand the 1960 dive depth. Or were there also some changes on the case design (on your photos I don´t see any case differences) or may be the material for the case was different in 1960 (e.g. alloy specification with higher yield strength)?

A really very interesting and exciting topic.....

Regards
Matthias