Most people will tell you to just bring less healers so each healer is sweating doing their own role.
This works, but is a risky endeavour. If you misjudge how many healers - or what healers - you need you end up constructing a situation where the healing is 'just barely' enough. Slightest misstep of anyone, and it's a wipe.
You don't want that. In fact I'd say we 6-healer Festergut, we could 5-healer it if the stars align - but we'd never be stupid enough to plan for that. Things never work out like they should, anyways. :P
So the easiest way to assign in more detail. If you have a Resto Shaman and a Holy Paladin on the tanks, have the Paladin heal both tanks via Beacon of Light and the Shaman heal the active tank. This works out nicely with the lingering damage effect bosses like Gormok or the cleaving bosses like Marrowgar. Alternatively have the Holy Paladin heal the current tank (if there's no split), and the Shaman CH over the tank to help heal the melee.
For raidhealing assigning certain spells can often work nicely. Resto Druid carpet bombs the raid with HoTs, Holy Priest uses CH whenever the timered raidspike happens, followed by PoH (prestacked Serendipidy!) on an assigned group, then flashhealing the remaining spikes. This reduces overhealing to the FH-spam at the end.
It's a lot about assigning healers according to the fight mechanics. If you know you're 3 healers, and for abiltiy X each has a specific assignment, you know what the others will be doing. If they aren't ,getting twitchy, crosshealing - talk to them. Especially Priests and Shamans can easily invest more mana&time into applied DoTs or the odd nuke, and every little bit whittled off the boss helps. These two classes should never truly run into boredom once their own targets are healed.
Last edited by KnThrak; 03-02-2010 at 11:26 PM.
-- (The Death of Rats, Terry Pratchett, Soul Music)