hmm..i think it's closer to correct now but not quite there yet. i'll do it again tomorrow night of course as you said. when i got it to 100 i turned the phone on, sent a few texts, whatever, eventually it dropped to 98, i restarted it on a hunch and sure enough when it came back on it said 99 again..but only for a few minutes then back to 98. so i think it's getting close to being calibrated correctly.
i mean it's not even a huge issue really, i can still get full charges, it's just a minor annoyance i suppose especially for someone like me who is a bit ocd about battery life
kinda wish i was rooted just for this, your rooted solution sounds a bit easier :P