Besides the RSA in macro mode at 70 mm, what else is work this lens? Nothing. I seldom use macro mode on many of my lenses, so this is a none issue for me.
I would like to have seen a comparison between the 24-70 F2.8II, 24-105 and this lens for IQ in non-macro situations.
I agree, if the focus shift is only in macro mode, then it's a non-issue. Macro shots mean manual focus, usually with live view. There will be no focus shift in live view with manual focus because the aperture will be at your selected setting while you focus.