Maybe you could combine Greg's RHD with the "pump it" drill.
http://www.network54.com/Forum/72052...secret+to+golf
(video halfway down the page)

This combination helped me ingrain the late release of the wrists.

Your wrist should still be cocked when they get in line with the thigh of your back leg. Also make sure that you are thinking about both wrists. The back of your left wrist should be flat-ish throughout the downswing and impact.