And what's the casting time on Healing Touch?

there, all updated.

What I think might be best (at least in fights where we only have to worry about MT damage) is to have 1 priest and 1 druid go all out on healing until they are nearly OOM. Then they are replaced and go have a nice sit down.

Sadly, no one in our guild can make Greater Dreamless Sleep Potion. Those would make the rest time more effective.

Obvioulsy I'm not much of a healer, but times I've been on raids healers would split into 2 groups (Priest/druid/pally etc...). 1 group would be on healing duty while the other would wait, and then when group 1 is low on mana group 2 would step in and heal while group one just sits back to regen...

Like I said I'm not the best healer so I don't know if half the healers can keep up a tank and possibly others getting hit etc...

Hi! I know I am brand new, but I thought I would add my two cents.

Having a channel for healers to broadcast what they are doing is exactly what we did in the guild I was in before I moved here. Anyone who wanted to know what the healers were up to joined the channel, and that's where the healers put all their spam. It worked pretty well. For the most part we kept everything straightforward, although a few of us did have amusing macros just to liven things up.

Anyway, it did tend to keep the overhealing to a minimum, and it always let me know when I needed to pop out of moonkin and lend a hand. And, generally, I reserved my innervate for whoever was the main healer to help cut down on mana issues.

During a raid, I watch the entire raid's health bars. All a healing channel would be is more spam going across the screen that I would never see. Over-healing is going to happen no matter what. My mods help, but nothing is going to totally stop it. And If one healer goes oom it's not going to wipe the raid. ;) We have enough alternate healers, innervate, mana potions and even mana regen that your mana goes up fast enough. Using a Demonic Rune, then a Dreamless Sleep Potion works well...as long as it doesn't get interrupted. Also mana oil is nice if anyone can make that.

I often do backup healing as necessary. If I see a health-bar dropping, I throw out some heals. I haven't thought much about over-healing, but the addon I use (SmartHeal) is pretty good and lets me know if someone else is healing my target (in which case I cancel my heal to save mana). It also has shift/ctrl-click heals and calculates which heal lvl to use based on the health of my target. A few months ago it had a few pally-specific bugs (it is developed by a priest I think), but it is working well now.

I second Lemmin's suggestions, and want to add some of my own.

For 5-man and under, I think what we're doing now is perfectly fine. A little overhealing rarely hurts anyone in a 5-man, and I just side-step if my heal is going to land and do too much extra healing.

For 10-man+ raids, I think two things are in order.

First, a healer channel is an awesome idea. It gives us a spot to talk healing and to indicate who is healing what without overloading the raid chat.

Second, assign roles to people and make sure everyone knows who is doing what. Have one person designated as the MT healer, and another who is designated as the backup. Depending on the encounter, you might have more than one rotation. Only the MT healer, whether druid or priest, heals the MT. The backup can either spot-heal if they have a lot of mana, or hold their mana to keep the MT alive. The rest get assigned spot-healing duties. Spot healing can be done by anyone on anyone, the dangers of over-healing there are less. When the main healer is unable to heal or out of mana, they say so in the healer channel. The backup healer then says in channel that they have them covered.

Let's say that Gleja is the main healer and I'm the backup. As Gleja drops below 30% mana, the coversation in the healer channel would go like this:

Gleja: Out of mana or unavailable to heal MT (Jorack), grabbing a rest. Noden, you're on the job!
Noden: I've got Jorack covered, Gleja. Enjoy your break.

The raiding group I was in used to use macros, changing the name of the MT and the healers as needed. You can also add a third macro for "I'm dead and never coming back into the rotation, good luck!" or it's equivalent too. The macros are used to ensure that the hand-offs go smoothly.

This way, the spam in the healer channel is less, but the same goal is achieved - less over-healing. Rarely would you want more than one healer on the MT - the chances of over-healing or under-healing (read: dead MT) are too great. There are encounters where the only way to do it is to have two healing rotations on a single MT, but they are few and far between (one in MC, one in BWL that I know of).

I don't like the idea of spamming what spells are being cast on whom in the healer channel, although I'm willing to try it. My expectation is that there will be too much information to process it in anything more than a 5-man raid, which is what the system is meant to help.

On a side note, I agree with Gleja's feelings that Benecast is a sin, and decline to use it as well. Y'all wanna use it, heck, go nuts - I'm not trying to push my religion on you, I'm just happy living it on my own.