For those that may not understand some of the highway mileage techniques mentioned, here is a picture of one application.
1) Set the left screen to Empower.
2) Run the ICE enough to raise the indicated battery charge level to almost full.
3) Moderate the throttle so the white part of the load display (far left) is only slightly above the blue battery envelope. Keep the engine running. Don't let it go into electric. This will take some work and your right foot might get tired.
When all of this is working you can get an instantanous mileage reading as shown in the picture (60MPG) depending on conditions. Provided the road is flat and you don't come across traffic, you can keep this up for a while. Remember that if the ICE load falls inside of the battery envelope, the ICE will shut off and you will be running on electric only. This may seem great but as soon as the battery charge level drops and the ICE restarts the instantaneous mileage will drop. Then, it will take more work to get back to the state you were in before.
So if I am reading this right, the ICE is charging up the battery, supplying power to the wheels and the EV mode is also working? I did not think of this before but the charging motor and drive motors are separate, I think?