Chart to chart you may be right - but you cant take out the glass from your real world uses
S
You're not incorrect. My personal experience, though, I can safely eliminate glass as an issue. Was using Contax Zeiss and now added Zeiss ZF/ZE's to the mix. I use the same glass on both cameras, so sort-of moots the glass arguement for me.
I say that because you also have to factor in the FOV or CROP between the cameras. It can get tricky. The 21/2.8 is incredible on both cameras, but of course the edge performance may "seem" better on the 7D because of the smaller coverage area. Using more of the center versus the Full Frame using much more. So the edges could seem bad, soft, etc etc.
ALl I know is I'm quite okay using that sucker wide open~