Each dungeon or raid is going to be different because of the mix of the group you are running with, so even if the boss fights are the same, the dynamic will be different and the healing needs will be different for each situation.
Heroic Lich King dungeons even more so as the boss fights get nutty.
Each class is going to heal differently, and as I only have experience as a healin' priest, I know that Discipline and Holy were totally different ball games, and when running as a Shadow, I know that Droods and Shammies also have different healing schemes.
Mods of course help, but the FACT of the matter is that no mod can automate healz, broham!
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