CDV delete does improve the clutch
release and subsequently the feel, it does not have anything to do with the transmission grind on shifts. Grinding during shifts is primarily a function of the synchros being able to spin up and match rotation speed. Spin up can be affected by the viscosity and temperature of the trans lubricant, the rpm difference between the input shaft (engine rpm) and gear shaft, the speed of the shift, and the design/condition of the synchros.
There are a number of variables to deal with when trying to isolate the problem. Since most of us are stuck with what BMW put in the car, for good or bad, we have to work around any of the limitations. BMW may have gone with a more robust and durable design (to include reduced noise production) which compromised the synchros ability to rapidly spin up, I don't know
. Like any other component, there is always a set of design considerations and compromises. Some manufacturer's have dealt with a similar problem by using a shift gate design which makes it near impossible to shift rapidly.
A large number of owners do not have the 1st to 2nd grind problem, but a few do. Some have resolved the issue with a change of shifting technique, some think that a different lubricant helped/resolved the problem. For some, nothing seems to work. And of course there is certainly a small percentage of transmissions which have an "out of spec" manufacturing problem.
As many have stated, the grind doesn't always occur and appears to happen only in the high rpm shift range. Maybe a specific and objective (no rants) "technical" thread which provides production date of car, type and frequency of grind problem, vehicle/transmission mileage, corrective action taken (such as lubricant change and type, warranty replacement.....), and the effectiveness of the corrective action would benefit all of us to find a common solution or at least minimize the problem.
I now relinquish my soapbox.