It is my understanding (and my observations) that the DSG is already in neutral when you come to a stop. It will have already selected first gear in preperation for forward movement but if you take your foot off the brake the car will not move forward immediately as per torque converter autos. It is also apparent when you take off on a hill. If it was already trying to go forward there would be no roll back between releasing the brake and hitting the accelerator.
So i would think it would make no difference if you put it in neutral or not as the gearbox is already in neutral when you are stopped.
Obviously these observations are only related to the two DSG's i have had experience with in my Jetta 147TSI so other DSG's may vary in later models or other driveline combinations etc...
1974 1300 Beetle, 1997 Golf GL, 2003 New Beetle Cabrio, 2014 Audi A4 quattro
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