so, today was my first day driving the volt to work...i'm working on contract away from home, so i won't get to charge every night. i charged before i left my house yesterday, then drove the 450 miles or so from PA to NC (stopping once for gas along the way). along the route, i used about half of my battery (til i got to the interstate, nearly all of the drive is highway), then put the car into hold mode. i stayed in hold mode until i got about halfway, at which point i got bored and started playing around...put the car into mountain mode and watched the battery recharge itself to fill the buffer. the trip also included a ride down fancy gap mountain, a very steep downhill grade which actually added another tick to my battery (and from the top to the bottom increased my electric range, according to the car, from 20 mi to 35 mi). once i got to the bottom of the mountain, i put it back into hold mode and drove on gas the rest of the way (about another 70 miles or so).
this morning, from hotel to work, i ran in battery mode...but when i went to the charge info screen (the one that shows mpg on this charge), the gas miles number was increasing - not the battery miles. is there something wrong here, or is the car smart enough to know that it was using miles on the battery that had been recharged by the gas engine while in mountain mode?