Healing is a very interesting experience, for me. You need a whole new level of awareness, as you're now watching what everyone is doing, and need them working in line to best do your job. Resource management is on a whole other level when you now have all of yours, the entire parties health and buffs, and whatever the boss has counting down.
It's a very active style of play, especially once triage comes in. When shit hits the fan, you need to decide who you can even try to save, and if they're worth saving. I've had times that I left a DPS on the ground because it was quicker to just start dumping all I had into burning down the boss, and grab 'em up after the fact.
Then comes in the fun of having multiple healers. You gotta work out who's taking what chunk, if and when you need to cover each other, and half the time you might end up healing the wrong people, because at some point you stop seeing the names. It's just health bars and cool downs. Nothing matters except keeping those bars just full enough.