Default [Q] one more battery question

I have searched xda-developers and many, many other sites that I won't list, and I get conflicting answers with every thread I read. Some of the threads are dated and hope that someone can give me a clear answer.

Like many, I have poor battery life on my VZW Galaxy S3 (non-rooted). It seemed to get worse after the 4.3 upgrade, but that may be a coincidence. I have read several posts that say deleting batterystats.bin can solve this issue. I have also read several, and convincing posts that debunk that theory.

I somehow need to find a valid solution to calibrate my battery. Here is the behavior I experienced today -

8:00 am - full charge and removed from charger
5:30 pm - 63% battery remaining; moderate use during the day on wifi the entire time (extremely pleased with this, yet very unusual lately)
7:00 pm - full 4g service from 5:30 - 7:00, but not on wifi. No usage during this time. Battery down to 33% (still not too bad after 11 hours)
7:05 pm - 3% battery without any usage, phone shut off
7:07 pm - plugged phone into car charger and immediately turned it on. Battery showed that I had 56% remaining. Disconnected phone from charger as soon as I turned it on and the phone was functional for 3 more hours on battery.

So, it appears that the phone is "thinking" that the battery has less juice than it really does and powers off automatically. I need a real solution to fix this. I know that people may respond with conflicting information, but I need a real solution or cause. Is deleting baterystats.bin really a myth (see: http://forum.xda-developers.com/show...p?t=2256038)?? Will running the battery down/recharging/running down/recharging/repeat/repeat/repeat really work?

background - Before my 4.3 upgrade (on 4.1.2), I used to get 12-14 hours consistently. I didn't install any new applications or change any of my existing application settings, but my battery life dropped to 5-6 hours between charges, and all with similar signal strength.

Any help or thoughts are appreciated.