From Ross-Tech Wiki

4.2 Can I use VAG-COM while I am driving?
We strongly recommend against reading data while driving -- that would be an accident waiting to happen. Almost everything that changes while you drive can be LOGGED to a .CSV file, which you can analyze to your heart's content using VAG-Scope or Excel (or a number of other programs) preferably while the vehicle is not in motion..:-)
If you find it necessary to read data while the vehicle is in motion, we strongly urge you to use a second person -- one to drive, one to look at the PC. This second person should sit in the back seat, because a laptop used in the front passenger's seat becomes potentially lethal if an airbag drives it back into the passenger's head or torso in case of an accident.