[Douglas Toltzman]

I have a tutorial on Toolfarm that illustrates a shot using the minimum amount of green screen.

Link to tutorial

Also, I agree with lighting the green screen below the foreground for a couple of reasons. One of them is that you can choke the key to avoid keying objects that are brighter than the background (at least you can with my chroma-key software, Vkey2). That way, your green reflections will be brighter than the green screen, allowing you to avoid keying foreground objects. Then by using green suppression (also built into Vkey2), everything will look quite natural.