Healers: Everyone on here has been saying you did a wonderful job. Maube whispered me today and told me how happy she was with your guys' performance yesterday. They're wrong. Your output is high but your survivability stinks. Some of you were just sitting still and letting lots of whirlwinds hit you. There is absolutely no reason for that. Ascoli isn't taking as much damage while Leo is whirlwinding, there is no reason for you to stand like a rock right next to Leo rather than running. Kleenk is the only healer I expect to have any trouble on this phase, and some of you are eating twice as many or more whirlwinds as he is.
For demon phase: As has been noted, some of you are having problems staying up and dpsing down your demon. None of you should have any problems dpsing it down. You've all got more than enough spell-damage in your healing gear to manage it, considering their vulnerability to holy. Make certain you're topped off before the demons spawn and with a HoT ticking if possible, don't park in some odd corner where no un-demoned healer can reach you, and you'll be fine.
That last point is useful for everyone. During the demon phase, stay near your healers. The warlock tank is usually taking 6-8k damage a spell-cast by that point and needs a hellacious amount of healing, it is very hard for us to wander around and find you. I'm really the only one that can walk around freely at all and I probably can't get to all five of you, particularly not when walking wide around the AoE blast from the demon's Chaos Bolt. I really, really hate it when I die because I wandered into it while trying to save your distant butt. Melee are the only ones who shouldn't be checking if they're in range of healers during the Demon phase.