[aerohead]

Originally Posted by RedDevil

The fact that your commute is so short makes the results even more impressive.
I don't come anything near those figures on my 22 mile commute, never mind the temperature.
But my Insight is still breaking in, and so is its steering wheelnut. Who knows, MMMV.

So ambient temperature does play a big role in the first 10 miles of a trip.
Before doing any ABA testing one should warm up the car for at least 10 miles, and probably much longer if the temperature is anything less than 24C / 75F (as your graph seems to bend at that point); otherwise the first A measurement would have relatively low MPG.

SAE recommends a minimum of 22-miles at 50-mph to stabilize all hyrodynamic loads at equilibrium for whatever ambient temp you testing at.