I know some of the material in this post will have been covered in other areas. I've very much appreciated the side-tracks taken in the Healing Trinket thread and the 2.1 PTR thread, for example, where healers go off in a corner and chat for a moment.

What I'm largely interested in is sparking a large-scale conversation about the current (as of Tuesday, patch 2.1) healing roles in end-game, for the four healing classes.

Firstly, let's set some parameters on this:

1) We're talking about end-game. Karazhan has some small bearing as a test case, but realistically, we're looking at 25-man content here. Maulgar, Gruul, Magtheridon, and SSC/TK.
2) Assume equal gearing, up to a certain level, while making an argument. Preferably, good gear. There's really no point in hashing over a comparison that has a shaman in blues and a priest in T5. Assume full (best) gear available to someone at the point of killing Magtheridon. Full T4, full crafted epics, all rep rewards available, and the best possible gemming / enchants.
3) Assume proper specs. While there is some place for a discussion about differences in specs, let's assume:
- priest, spec'd at least 35 points in holy, with access to the raid buff of Divine Spirit
- paladin, spec'd at least 31 points in holy (probably 41, but there are some interesting variations), who wasn't stupid enough to stack 40% crit on his/her gear, and has a proper blend of healing, Mp5, and spell crit
- shaman, resto
- druid, either full resto or 27/0/34
4) Let's assume intelligence in raid design. Set a maximum of 2 shadowpriests to the raid, and remember that raid leaders make intelligent decisions about who gets access to those SPs. Assume one resto shaman (min) for a mana tide. Etc.

Now that we have that -- what synergy should be used for raid healing? What sort of spells would you use to work TOGETHER to do the job of keeping the raid (and mostly the tank(s)) alive? What classes work especially well together?

The motivating cause for this thread is a discussion (argument) I had with my brother, who plays a 70 holy paladin. I tried to (badly) explain the thought behind paladins not using FoL as a whack-a-mole tool, as it overwrites druid and priest HoTs, and results in our heals being less effective. He seemed to think I was telling him to not heal, and got cranky and ... ya, anyway.

Take a test case, and talk about what people should be doing. How do they work together? What's the best way for the classes to synergize?

That sounds more like a problem with healing target organization than anything else. A paladin should never be raid healing if it can be helped. They are the most specialized single target healers so put them on your main tanks and teach to only heal that one target Patcherk-style. Druids and shamans are awesome for raid healing. Priests can do either. Try to organize your healing so that HOT classes don't overlap with direct heal classes.

For example on Gruul I'd stick paladins on the MT/OT, druids and priests on raid healing.

Well, basically. Do proper healing assignments. You would be amazed exactly how much raid healing one shadowpriest-fueled resto shaman or a tree druid can do if the rest of your healers leave them to it. paladins should be on tanks at all times, and if that leaves you with excess healing.. spec some more druids/shamans/priests dps untill its not a problem anymore.

Do paladins remain the best choice for MT healing in 2.1? The chances to Illumination and to Spiritual Attunement remove a lot of the former synergy that allowed paladins to do the FoL->HL spam that formerly was their forte. At least, that's what's being claimed by my guild paladins.

If you had equal numbers of holy priests and holy paladins in a raid ... what should you do with them?

The obvious power of a resto druid or a resto shaman to do raid spot heals should never be understated -- we're currently trying to *find* a resto shaman, to put in just such a role. But as raid healers, we had a lot of success using paladins in AQ40 and Naxxramas, with the druids/priests covering the tanks. It was a different raid environment, but it worked -- paladins using FoL to top up 40 people, while druids kept HoTs / Swiftmend going on tanks, with priests doing big "nuke" heals to keep them topped up.

Obviously fights like PW are different -- I'm more referring to non-gimmick fights, where the raid takes damage.

Additionally, on Gruul : atm we take 4 paladins, 2 holy priests, and 1 resto druid to this fight. From 1-8 Growths we have the druid HoTing people, and basically just topping up shatter / cave-in damage. The paladins/priests are all assigned to either OT or MT, and just keep them topped up and keep their mana high for the 10+ growths area. From 10 on, the raid is told that they are on their own, and to lrn2consumable.

What I've personally experienced is that bringing 7 healers rather than 8 brings down the overhealing, and still manages to keep your raid up. As for setup and healing role I think it should be somewhat similar to tiberion02's suggestions, with the exception of 1 less shammy so there is only 7 healers. The tree druid buff is nice to have, but if you want another priest then a healing druid isn't really needed imo. But yes for healing roles, have the 3 paladins tank heal. The priest(s) can do whatever is needed, and the shaman aswell as the druid can raid heal, because that's what they are designed for it seems.

As for the way you heal on Gruul/Magtheridon (which is the only encounters so far I've healed on), I'd say as a priest, that just going anywhere near your flash heal button is strictly forbidden. The mana ineffectivity and healing per sec of that spell is simply too bad for those fights. If I'm raid healing I usually chuck renews on everyone that needs it, or maybe a Greater Heal if needed. Prayer of mending can be utilised with great effeciency if it's a raid damage heavy fight. Now for tank healing, which I tend to do quite a lot, chain spam greater heal, and cancel it if it isn't needed, works great for me, and I usually beat everyone on effective healing when healing MT on maulgar. Gruul is a bit more complicated because you have so many healers healing one target, and what you have to prevent is the high crushing blow kills. This creates a lot of overhealing, one way to prevent it is anti-overhealing addons (VisualHeal, Healcom), another way is simply to keep your eyes open and have a /stopcasting macro ready (NO JUMP ISN't GOOD ENOUGH :P). Sometimes using a bit of Prayer of Mending in the start to help the tank gain a bit of agro, proves to be really good. I don't know how much the encounters after Magtheridon differs from these... And as said earlier FoL spamming paladins is a nono, they're the most efficient single target healers and should be used for that solely. If I was to design our usual healing setup for Maulgar (which I'm not =() it would be something like:
Maulgar Tank: Paladin, Priest
Mage: Paladin
OT (Usually 2): Paladin, Shaman
Hunters: Shaman
Raid: Druid

Guess that was my impression of healing roles so far.

Our guild has just started working on Hydross. What do you think would be the ideal healing setup for him?

Edited for grammer.

1 healer watching water tomb/vile sludge. Resto shaman is the best for this role.

1 healer per offtank while you are killing the adds, and 2 or 3 healers on the main-tank.

Healers switch to the main tank as the adds are dead, it is very very taxing on mana so group your healers with a shadowpriest if possible.

I'm curious, why a druid?

I've always found that priests are easily the most effective for that. The only raid damage on hydross comes from the sludge and ice tombs. Renew for the sludge, PoM + Shield (emergencies) for ice tombs.

We usually have 3-4 pallies on the MT full-time, and then 1 priest on each add-tank that watch the raid as well plus a druid that keeps HoTs on everyone taking damage. If we have a resto shaman they keep earthshield on the MT and spot heal wherever is needed (usually take the spot of a pally on the MT).

Perhaps a starting point to address your more direct question, is to bring to light the nature of HOTs in raid environments. While clearly they(HOTs) have situational use, they are not in and of themselves effective tools for raid healing 90% of the time. I don't think I need to specify on that note, but in case someone is particularly anal, Hydross/Fathom are good examples of where hots can really be effective. Anyway, the point I'm getting at is this; Time and mana permitting, it is always better to have people at full health, than not. It seems like a stupid thing to say(in that it seems obvious), right? But it isn't, and it leads to the arguement you had with your brother. If he had both the mana and time, to bring XX to full health without risking the life of another raid member, then it is in the best interest of the raid for xx to be at full health as soon as possible - Even if you had a HOT on said person that would over time result in the same end -. By that logic, using HOTs to try to accomplish what straight heals could, or for that matter, will anyways(your example) accomplish, is an ineffective use of both time and mana. That said, given the nature of the paladin class, it is in fact something that should be cherished, not looked down upon. As a rule, in a raid healing environment(8+/- people doing a similar job), people will heal people regardless of what group they're in, who they are assigned to heal(with clear exceptions), or what affects the healee currently possesses, and it isn't a bad thing. While it diminishes the potency of HOTs in many ways, having your raid healed to full faster is in everyone's best interest.

In short, HOTs by design are intended to mitigate predictable and consistent long term damage, and particularly damage that is received in the same form(DOTs(Hydross)). If damage can be effectively(that is at similar mana cost, in less or equal time) healed by other means, then HOTs are not the solution.

Now, I do however understand your base concern(having your toes stepped on), and while it can become a rampant problem, is one easily remedied by effective healing assignments. For example, you're a priest healing a non-mt tank on hydross. You start up a gheal for your meat shield, and a mere moment before it hits, some paladin has dropped a flash on him resulting in your cast healing perhaps 1000 damage if you're lucky. He shouldn't have done it. He wasted both of your time, as well as your mana. You can't switch to flash heal, because then you would be wasting your own mana. Give him a job, make sure he understands yours. His primary nuke heals 2000 hp, yours heals 4000, and you think about deficit in different terms. Simply explaining that, coupled with clearcut directions, can fix the problem quite quickly.

To the mentioned idea that paladins are not effective raid healing, and should not be allowed to utilize fol in such a manner, I couldn't disagree more. An extremely fast, extremely high hpm spell is bad for that role....how? The efficiency of the paladin class does not change based on the suggested parameters. In an ideal situation they would be doing the same thing to a tank, that they would be to the raid. Moreover when directed at the raid, that paladin's OH would go from what is generally 40-60%, to well under 20. My point is, to suggest that paladins are not effective raid healing is quite misguided. Their regen is static, their heals are fast and cheap, and they can essentially fill any role.

Anyways, having said that I will certainly agree that paladins provide a strong core for a mt healing group. The synergy between a paladin and a priest in such a situation is undeniable. Strong well placed gheals backed by consistent fol in the 2k range, and hl in times of need, is hard for any mob to contend with.

I am the healing lead for my guild alliance's second raid team. We've just recently fielded the people to start up Gruul's lair, and as such we've had a little bit of a rotating casts with some flakier people, and Mother's day. We downed Maulgar this weekend on our third night of attempts.

As it stands, our healing roster of regulars is supposed to be:
1 Holy Paladin
4 Holy Priests (2 Dwarves, 1 Draenei, 1 Human)
1 Resto Shaman

Also available we have 1 Prot Pally, 1 Feral Druid, 2 shadow priests (Human), and an enhancement shaman.

I am trying to keep my head out of the priest emo game, and I realize that we're a little "low" on healing in general, but our non-specced hybrids have been very good sports about healing during Maulgar for us so far. I'm looking for ideas to make this work as we push into deeper content with a weird healing team. In particular, the high amount of holy priests (diminishing returns on stacking the class) and lack of a resto druid period bugs me.

The raid is a mixed group of our raiders from pre-BC and some newer people, so we literally range from some of our Naxx crew to people who didn't raid, or rerolled for BC. I am confident in my crew's abilities, but I think we're facing a bit of an uphill battle.

I'd love to hear so ideas on how to make the most of these guys, and we've got some good-natured and flexible folks among us (one of our shadows respecced just for last week's raid since we lost 2 healers that night). I also have a level 70 druid that was my raiding main before BC, and so it's within the realm of possibility for me to play her instead if 4 priests and no resto druids is really going to break us. I'm open to compelling arguments.

We unfortunately only have 2 paladins total that are on the regular roster. We have a few other accessible ones, but there some scheduling issues. I would love to have a third pally, also.

If I were to switch to druid, it'd be with a full resto tree build to utilize HoTs and swiftmend, and not a HT balance build. That'd be kinda silly to replace a priest with, a green leafy priest for functional purposes at that point. (additional innervate and rez aside). As it stands for me, I've raid healed on everyone but a shaman in one place or another, and since each class has its place in a healing team, it's not super important which raid healer I play. 5mans make much more of a difference, IMO. We even have 2 dwarves in addition, so we don't even hurt for Fear Ward.

Since we already have 2 shadow priests, is a third really that valuable? We don't have many more mana users to put them with, and unless we pull another healer out of someone's bum, I certainly wouldn't want to sacrifice one of our only 6 healers for it.

So far, I've kept the priests to heavy tanking healing, the paladin to mage/MT/OT healing, and the shaman and feral druid to raid healing.