Personally, I use Hibernation ALL THE TIME. It's actually become my favorite heal. Think about it this way. Its a 1 second cast.... its not using much mana at all, and it is our most powerful heal. It heals more than Natures Elixir and usually more than BITF will heal at sub 50%, and as an added bonus, that heal goes to the WHOLE GROUP. Depending on your group makeup, that will essentially allow everyone in the group to manastone as much as they want, use any power conversion spells they want (necro, wizard, etc..) and also classes like necros who can ues their health to heal, can do so freely on a rough mob if they need to as they know they will be healed with the next hibernation. On raids, its extremely useful while in the MT group, as its a very fast cast time.... and while spam healing youll essentially get a "free heal" when it does go off. One place I use it a ton is in Poets while fighting the keeper, as he sometimes will spike damage, if im the only healer, it helps to have the extra 1300 heal come in while i'm spamming my other heals just to get the tank back up. Also, combined with HOTs, it allows you to porcupine and still be healing quite a bit. Overall, its a great spell and I use it as much as I can.