Aerodynamics/Drag Coefficient

Notice, both the front and rear wheels are spinning when Toyota test aerodynamic and rated it as 0.24 Cd.

 

My guess here is the ice is efficient over a larger power range, the motors/psd allow engine off to a higher speed (110 kph (68mph)), the battery provides more power (they say it charges 28% faster, not disclosed peak power) allowing easier programming to stay efficient. I doubt they found any magic algorithms that they could place in a gen III system, they needed the new hardware.

Active shutters simply allow for easier warm up and should be included in the vehicle portion, although that isn't spelled out. It looks like about 4.5% lower drag (using the lower frontal area and 24 versus 25 cd). rolling resistance looks to be down about 5%, which means those two probably count for 2.5 mpg better. if the total is 5 mpg better, the hybrid system management and the more efficient engine would each account for around 0.7 mpg. Motors/PSD/Transaxle/battery/etc for 1.1 mpg. Looking forward to official epa and contributions to that, the jc08 may be very different, but if it translates those are the numbers.