Agree with what you said mostly. The energy efficiency of EVs are also definitely vehicle dependent (brake regen design, power to weight ratio, power module design, motors, power electronics). I drove an i3 before and was getting 4.6 avg m/kWh and a few times that I've been testing Honda FitEV, that went up to 4.8-5.2 m/kWh without me changing my driving style. But since EV has full torque for the entire range of allowable RPMs, driving aggressive is easier and more manageable. In some of the strong regen EVs like i3, I can get it hover at around 4 m/kwh even with a fairly aggressive driving style (first shooting out of the red light stop, last coming to an stop at the red light etc.)

Also get 4.2 miles/KWh here. Maybe they will build in some kind of feedback for the trucks. The leaf has (had) the little trees that appear on the dashboard; maybe UPS can track this and issue a token incentive (free meal, bonus) at the end of the month if the delivery schedule is accomplished with less energy.