The main problem lies in the fact that Thok's Deafening Screech is about once every 2.4 seconds, which is the same cast time as my Prayer of Healing. Squeezing a PoH in between each Deafening Screech is nearly impossible. I am using Power Infusion to reduce several cast times down to 2 seconds, but after that, I need help.
What I am doing:
Divine Star, keeping PoM up, Power Infusion + PoH, and Penance off CD when I'm not using PI for PoH's. I also throw down Barrier, however I am debating whether to use it for Screeches 6-10 or 8-12.
My raid team 2 heals everything, so it is crucial that I maximize my heals on this very healing intensive fight. Their previous healer was a druid. He could cast Rejuvenation freely without the fear of being interrupted. But as a priest, my primary aoe healing is a cast, and a long one at that, so this fight is much more difficult for me. Currently I am only able to push out 114 hps. I see some ranked disc priests pushing 200+. I must be doing something wrong.
Short of spamming Shields after PI wears off, what can I do?