Brian, Thank you for posting the Pop Photo test report excerpt. Norm Goldberg's test reports of cameras and lenses blow away most so-called "tests" that are available today. Not only did they assess the performance of the lens/camera, but he disassembled it and commented on the engineering choices made by the manufacturer.
My copy of the 55/1.2 K is a wild ride of aberrations at wide open, and then becomes an unusually "sharp" normal lens at f/4 and f/5.6.