Tim, Do you use Go times with an L2 charger? I'm using the factory level 1 and it really doesn't do much to preheat the car, but I can't justify buying a L2 with gas at $2.39/gal right now (and the L1 charger is fine for the overnight charges given my driving pattern).
I have blocked my middle grill with foam pipe insulators to help keep the coolant warm.
No, I use the level 1 charger and park in a heated underground garage at night, so the car interior is warm (65〫 ) when I leave for work. I have the temp gauge and split power displayed on the My View screen, so I know when the coolant is warm and when I'm using battery or ICE. By the time I switch to EV, the heater has come on full and I turn it down to setting 2 or 3 depending on the temps. The ICE comes on when the defrost condenser is on, so like I said, I try to use defrost as little as possible. I like the idea of using the foam to block the grill, good idea. With slightly warmer temps this morning and following the same plan, I used 0.08 gallons of gas on my drive to work today.