Hybrid, also spell crit aids healing spells also...
Just to take this apart, there are no Hybrids where large scale raids are concerned (or every class with healing capability is a Hybrid - take it as you wish). Basically in 40 Player PvE raids all classes that can heal are generally expected to heal (with whatever additional unique support function each class provides). The Tier I, II and III Raid sets are designed to enhance large scale raid capabililty and generally specialise each classe into a designated role. Frankly for a healing class mana regen and + healing are probably the key stats to improve.
Now this isn't to say any healing class (Priest, Druid, Shaman, Pally) can't play a different role within a large scale raid. But generally you build a raid around 15 Healers, 5 Tanks (generally Warriors as even the best equiped Druid / Pally / Shaman can't out tank similar equiped Warriors) and 20 DPS. If you want Shadow Priests, Feral Druids, Elemental or Melee Shaman then you really need to replace Rogues, Hunters, Warlocks, Mages - and lets face it, a Healing - DPS class shouldn't really be able to compete with equally equiped pure DPS classes - if they can, why the hell even have pure DPS classes? So in short, the raid sets have alwasy been designed to enhance raid performance and thus will always pigeon hole classes into a certian role.
As for the +crit thing, really depends what class you are. If every healer assumed a crit and adjusted thier healing accordingly you'd have raid members die left, right and center. Most of the time crit healing is an added bonus but usually not that needed. The only healing classes that gain any real benefit from crit heals are those that gain a funciton of their mana back after a crit. For the rest of us, a majority of the time all it contributes is overhealing.
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guild im in now is basicly dead anyways
