When used at close range even what is in focus won´t be as sharp as it would be with a Macro-Planar or the like. Have a look on my "In the Garden of Sanssouci" and look at the flower. Sharpness is really low with this lens if used wide open at close range. I find the bokeh to be particularly beautiful for a wide angle though!
There is nothing wrong with my sample in this regard I think, as I said, it performs superbly when used at infinity.
I think this is why Zeiss added the FLE in the later generation.