Canon's sharpest lens

What is Canon's sharpest lens?

First, I know that the term "sharpness" is a bit vague especially when MTF values don't always show softening artifacts such as fringing etc. (AFAIK). Also some lenses are sensor out-resolving sharp in the center but gets relatively bad towards the corners (e.g. 24L stopped down).

But if anyone asked, what would you call "Canon's sharpest" lens? Here are my nominations:

• 135L @ f/5.6 (closely followed by 85L @ f/5.6)

• 300 2.8 IS @ f/5.6 and 200 f2 IS @ f/4

• 70-200 f4 IS, 200 @ f/5.6

About the zoom... I do admit that I'm a firm supporter of it but the reason why I added it to this list was because the top scores it has consistently demonstrated on review sites and because of with my own experience comparing it to the 85L.

What are your thoughts and experiences?

GTW
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