the screen is always the biggest battery drain for me. I do remember when I first got my DRMHD the battery was good, but not as good as it eventually became. The OTA Jellybean update improved battery significantly. I make no attempt to spare battery in anyway (constant gps, wifi, 4G, several widgets, all push notifications) other than the display which i set for automatic brightness, which i now prefer (if i switch to full brightness its a strain on my eyes) and i can't run this thing below 50% battery no matter how much i use it an 18 hour day.
Everything I've read suggests that its unlikely any battery conditioning methods are necessary, but I do know my battery preformance improved after a couple of weeks with the phone.