I gave an honest rep to the situation...
ABSOLUTELY... the MDS shuts off at the slightest incline and the mpg reading does drop off....
The PROOF is a good MPG read on a trip ... I’m planning a trip to the Keys ... and Alligator Alley SR41 has a speed limit of like 55.
In your previously posted picture I could see the RPM, which was about 1650 if I recall.
If instead of MDS and 4 cyl mode,
running all 8 cylinders
with a geartrain ratio that puts the engine at about 1200 RPM
with VVT changing camshaft specs to optimum
would give an even higher MPG.
This would also let the vehicle climb a steeper hill than what MDS can do in 4 cyl mode.
But...... on an even steeper incline
or when wanting to accelerate and pass another vehicle,
the driver In 8 cyl mode would feel the slight jerk of the needed down shift,
but MDS goes away with minimum jerk.
Over the life of the vehicle MDS probably wastes 1000 gallons of gasoline
compared to 8 cylinder with optimum gear ratios.
Is it worth this wasted money to avoid the....gasp....horrible mental pain of more frequent shifting?
If you understand engine BSFC (brake specific fuel consumption) maps,
you are very accepting of more frequent shifts, it gives you peace of mind.