Strange. Lucky guy! Do you wipe before you flash a new build? What do you wipe? I wipe everything for huge updates and get this problem.
i experienced that dalvik cache wipe is necessary when i was updating part of rom, such as framework, camera app, etc. so, it may not be necessary for rom update, but i wipe dalvik cache once in a while. i used to wipe cache as well, but not any more.
well, i would say i am lucky. after all, i still get charging BSOD once in a while. i will try to test battery consumption again, but i think 36 hours usage per charging is pretty good for this kind of hardware.
edit: ok, so i tested battery drain with respect to sensor usage: screenshot at
http://www.mediafire.com/i/?c2qzcuueci83vcp
first 3 hours w/ sensor disabled, rebooted, second 3 hours w/ camera, gallery, map apps run, third 3 hours w/ sensor enabled back.
for the first 2 hours, wifi was off for some reason (i move from subbasement to ground, and wifi gets lost sometimes), and that is why drain is slower, but once wifi is back on, the slope is exactly same as the other two portions. it was unfortunate that i only have 1 hour of the first test, but i think it confirms that sensor usage logging may not be exact reflection of battery consumption. you can do a similar test, and see what happens.