Errr... I'm thinking maybe my math is wrong by a lot. I'm assuming someone has calculated the following already, but here goes:
Based on a recent odometer logging including 3 partial charges, the car reported 142 total miles and 62 "EV" miles, even though "pure" EV miles (battery charged from wall) had to have been around 45 (though I didn't measure) based on my typical miles/kWh in these conditions and total kWh discharged. So really there were 142-45= 97 hybrid (non-plug-in) miles. My "stealth EV miles" were 62-45 = 17.
Therefore, in hybrid mode approx 17/97= 18% of my total miles were "stealth EV miles." Applying that to my odometer reading of 82,000... that's 14,760 miles. 16,300 - 14,750 = 1,540 miles charged with an EVSE. 1540/4 = 385 full charges over 4 years, or 2 per week. Maybe this is more accurate...
Also, this was a fleet vehicle for 4 years... so that might explain it. Just a clueless purchasing agent wasting money on a giant battery that I can now enjoy with little degradation???