Post by Aldones
I just started playing again after a 2 year break, but I can't imagine healing has changed that much in MoP raiding. Healing has never had much of a rotation. You have two types of healing: reactive and proactive.
Generally, most healers starting out heal after damage has taken place. Makes sense, right? However, with experience you can learn to predict damage and either start a cast so it goes off soon afterward, eliminating not only reaction time, but part of the cast time (you can always cancel a heal if necessary). Likewise,
Power Word: Shield is 100% proactive as shielding just wears off if the ally doesn't take damage. Still, ideally it's placed before they take a damage spike.
As far as a "rotation" is concerned. Hopesedge gave a reasonable explanation based on hps. Use the cheapest spell that does what you need as fast as you need. Try to mitigate your over-healing, i.e. don't throw a
Greater Heal out when
Heal would suffice. They both have the same cast time, but have a 12,000 difference in cost. Don't throw out a
Heal when
Flash Heal is needed for the casting speed.
Make extensive use of
Penance and
Power Word: Shield.