But before I get there, let me define quickly what it is.
Over healing is the act of excessively healing damage that a player has taken. So if a player is down by 5000 health and your heal lands for 11000, then you've over healed that player by 6000. As such, the extra 6000 is then considered wasted.
Over healing is bad
Efficiency. This is the view of players who believe over healing is a bad thing. They don't like wasting mana. Every point of health restored should mean something. No heals should ever be wasted. Healers strive to use the right spells at the right time in response to different attacks. There is an underlying belief that it is all about the efficiency of spells.
I've seen raid leaders and healing leaders point to over healing meters as an indicator of overall bad healing. It's one of those unbiased signs and a typical lambasting proceeds something like this:
"You're over healing too much. Because of that, you're costing us the kill. We're going to have to replace you with another healer who doesn't over heal as much and knows how to control their spells."
Alright, maybe that example was a bit too dramatic. But there are some players who do take it to that extreme. Part of the reason is that over healing is a symptom of bad mana management and such. So the more over healing a player does, the more mana is being wasted. Mana is a precious commodity for us and it shouldn't be thrown aside like that.
At least, that's the prevailing theory.
There's nothing wrong with over healing
Here's the other side of the argument. Do whatever it takes to get the job done. In this case, the primary goal is to make sure your tanks or impact players (anyone who's important to the fight) do not die. There is an understanding that bomb healing is a necessity at certain points. Obviously the negative side of this aspect is that healers will cut through their mana fairly quickly.
Besides, most fights don't last that long anyway for mana to truly matter.
Okay, so let's get back to the question at hand here. Which school of thought is correct and which one isn't? Does over healing truly matter? Is it an indicator of a bad player? The correct answer is it depends. Like any other question about healing, the answer is always going to depend on context.
A quick history
A long, long time ago in raid instances not so far away, over healing was a predominantly bad thing. The game mechanics were different then what we have today. Managing mana and healing back then was extremely micro intensive. Pop open your spellbooks, and you'll see different spells have different ranks. It was fairly common for healers to have a rank 2, rank 5, and the max rank of Flash Heal. Multiply that by Greater Heal and Prayer of Healing (I'm using my Priest as an example) and it populated the keybinds by a good amount. Another thing is that casters were allowed to chain chug potions. We didn't have replenishment either. We had to farm hours on end for Mana Oils or Dark Runes especially if you were on a top raiding guild. May as well call it Grindcraft or Farmcraft or something along those lines.
Anyway, the issue I wanted to get at here is that over healing actually meant something during this period in raiding. Raiding then is different then it is now.
(As an aside, I heard rumors and myths of a notorious Priest on one of the servers I played on. Back during Molten Core, he'd consistently receive props for doing a large number of healing. Unbeknownst to everyone, he was standing at the entrance just healing himself the entire time!)
At the present
The raid bosses are slightly different now. It's up to each individual healing class to determine how long they can go with every possible buff and flask they have at their disposal.
Try this. Heal yourself or another player with your max rank spells and find out how long it takes before you run out of mana. Most raid bosses nowadays have enrage timers. Gone are the times when we had 20 minute fights with Illidan. Enrage timers are shorter now. Some encounters even have soft enrages.
There are some fights where you just have to let go and blast everything. What difference does it make if you end the fight with 90% mana in the tank versus 5%? The thing about healing is that it can be a delicate balance to many people. You don't want to run out of mana. I understand that. But what's the flip side? You don't use enough of it resulting in player casualties.
How nit picky is it to go after players who are over healing? What's the alternative? They under heal? I never really understood that. At this level of content we're facing, we just have to blast our tanks.
The only time when over healing becomes a problem is when your healers run out of mana. Even then, as a raid leader you need to ask yourself why. It could be a gearing issue. They could be way out of their league in the content you're working. More often not, a simple healing assignment switch can help resolve that. Or the problem could be deeper. Most encounters have the raid taking X damage. Your healers have to be able to heal X (well, give or take) to successfully get through it. If there are ways to avoid damage, then emphasize it.
It's always been easier for me to dial back on healing output once I get a feel for an encounter. Figure out what your limits are as a healer. That's when you can gradually scale down if you find that you're over doing it.
Want some more advice for working with the healers in your guild? Raid Rx
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