see, setting the required boost at the right levels, makes it work on the best possible RPM range. and thats where you extract the maximum out of it.
AFRs, ignition timing and VTC has to be adjusted accordingly in all that load conditions.
we need to find the sweet spot for CVT by adjusting other parameters. and that's where the car gives the best time.
but that setting can not be the same for 0 to 100 or quarte mile or 100 to 200
for all above mentioned three conditions, settings will be changed.