[mosc]

first, you should realize that NN knows more about this than you. Second, you should learn what your fuel system and transmission are actually doing when the car's in neutral. You will save gas by leaving it in gear and it will also be easier on your drivetrain.

When you put it in neutral at a high speed, the ECU immediately starts throwing more fuel in. You can see this if you log the car. The LEAST gas for any speed is when the car is in gear and the gas petal is not depressed. Also, this saves brakes because the car will naturally slow down. It is true that this does wear slightly more on certain parts of the tranny BUT...

When you put the car in neutral from some significant speed, the drivetrain is still spinning. The transmission does not stop instantaniously, it has a lot of inertia. If you then come to a stop and want to put it into first, this is a MAJOR change of speeds for the still spinning transmission which is not good for it. If you had left it in gear, it would slow down on it's own until you got nearer to 0mph. Then, it's much less of a shock when you switch into gear. AWD trannies break more out of shock load than wear so this is the more significant wear to worry about IMHO.

Basically NN is telling you that you're doing something stupid that's costing you money and hurting your transmission and you're telling him he's a jerk...