You all need to explore: Dungeons can be cleared with 4 healers, 4 tanks, 4 dps, 2 dps 2 healers, 2 tanks 2 healers, etc... Going with the traditional 1 tank, 2 dps, 1 healer is simply what dailies do to keep them fast and simply easy to complete. Dungeons are meant more to tell a story for the Lore rather than keep people grinding them out on a daily bases to get better at them. It's simply not the way the game is designed. You go into a savage raid, bloodwhetting isn't going to keep a tank alive, the boss's auto's alone do more damage than bloodwhetting can heal.
What needs to be fixed is raid design or dungeon design. A bit of complexity doesn't hurt, but people forget that a casual group struggled on The Burn. They had to nerf that dungeon cause the Fog Dragon was killing more people than pvp (insert sarcasm). Healers have a aoe button for a reason, use it. The basics of dps: ALWAYS BE CASTING. If a tank isn't taking damage in roulette, DPS. If a tank is taking damage- heal it's that simple. A lot of healers in this forum must not have Glare III, Broil IV, Dosis II, or Maelific III on their hotbar in dungeons and stand around doing nothing.