I don't know who these people are who "cannot shift smoothly". We left the CDV in place on my girlfriend's 330Ci, and we both shift as smooth as glass, in spite of the fact that we've both been driving manual transmissions for over 40 years. A clunky shift on these cars is either pilot error, or there's something mechanically wrong, such as a worn throw-out bearing. Our 103,000 miles with the CDV in place show that the CDV doesn't cause rough shifting.
Edit: And the original clutch is still in the car, so it's not exactly worn out prematurely. By the way, I'm a (relatively) conservative driver, but she's not - she drives like a bat out of hell. I have to work at it to keep up in my 545.
Engineers do it with a torque wrench
Last edited by Wolrab; 11-15-2012 at 01:43 PM.