Not sure. Maybe the app optimization doesn't necessarily clear out any of the old temporary data stored in the system cache.
What I do know is that after the update and then wiping the cache partition, my standby battery life has been improved so far. I'll see if that persists.
Well, looks like mine is whacked. I am back to losing 25% of the battery in 9 hours of standby with ZERO screen "on" time (instead of 3 to 5%). It reports 56% "Android OS", 15% "Google Services", and other 30% in various little stuff. I am going to try clearing the cache partition now
