I believe this is the correct term: clutch diverter valve; keeps you from dumping the clutch etc.

BavAuto has the valve but with no guts inside. They say it prevents the passenger head bobbing syndrome when you let out the clutch. An article in the Roundel magazine says it helps the life of the clutch by installing the aftermarket piece.

Anyone had any experience with this? I'm pretty slick with a manual shift but this clutch keeps me on guard all the time. I find myself slipping the clutch to avoid the herky-jerky motion.

See, the questions never-never end here!