Emissions can benefit when you tune for something else, but I wouldn't call that tuning for emissions.
My point is that if you don't care about emissions, then there is nothing to trade off. A computer controlled system can be tuned entirely for mileage at low power output and also tuned entirely for power at the high end.
My point is that if you don't care about emissions, then there is nothing to trade off. A computer controlled system can be tuned entirely for mileage at low power output and also tuned entirely for power at the high end.