For black & white, contrast is not controlled by the taking lens. Contrast is controlled through film development and printing.
Originally Posted by puketronic
How critical is an uncoated lens? Color photography was developed before lens coating. Take a look at old, well-preserved color photos, and see the effect of an uncoated lens. Do you actually see a problem?
Contrast lost through lens flare is always a problem. Somebody posted a link to a test where a box with a test target in it was photographed against the sun. The test shots were made with and without a lens shade. The photographs with the lens shade showed much better shadow contrast and detail.
What you need to do is make tests for yourself, and see what works for you.