However, you are testing not just the lens performance but also focussing accuracy
all shot at 250 F8, so reasonable depth of field, I doubt focus accuracy was a big variable, although I agree as the Werra was the only zone focussing camera of the 4, it could be. FWIW, the result does tend to bear out what could be expected, as the Tessar in the Werra is only a 4 element lens, as opposed to the 7 element Sonnar clone (Jupiter 8), the 6 element Schneider Kreuzenach in the Retina and the 6 element Zuiko. However with a 35mm neg enlarged to 24x20 I can still barely tell the difference on the prints, so real world outcome is any of these 4 cameras are very capable. Enlarger lens is a componon-S 50mm/2.8 BTW.