I would think that it would actually help since you can upshift at lower rpms but Im just seeing who keeps it in full automatic and who actually uses the "manual" shifting and if it has improved your FE.
My new (to me) Passat TDI has the tip. Not as useful as I had hoped. The engine and transmission electronic 'brains' limit the options available. In full auto they have total control. In 'manual' they maintain "veto" powers over the driver's request.
Full auto will not shift into 5th until 42 mph (speed controlled, not engine load controlled) and will drop back to 4th, absolutely without regard for accelerator pedal position or coasting or downhill conditions, at 40 mph.
It's not as if the engine doesn't have enough grunt. It's at 1500 rpm and well up into the diesel's torque curve, so "lugging" isn't the concern.
'Manual' will not permit activating 5th until 40 mph under any conditions I've yet tried, and will drop back to 4th, without driver selection, if speed drops back below 40. Once my request for 5th has been over-ruled the trans remains in 4th forever or until the speed is once again back above 40and I additionally submit yet another request to please let me have 5th again.
Pretty please with ice cream?
Oh, come on damnit! I'm almost coasting, here! Gimme 5th!