A month and a half ago, I felt the need to sum up my thoughts on raid healing as a resto druid. I did so in this post:
Since then a few things have changed. Here is my new spec:
In addition to this, I swapped out Glyph of Regrowth for Glyph of Nourish.
My reason for going this route is because I have seen a lot of resto druids singing the praises of nourish as well as seeing how nourish has been buffed recently. I also see a real failing in my previous build because any single target healing on a tank taking heavy damage is very mana intensive and extremely dicely. I experienced this first hand in 25 man Ulduar in Iron Council. I was asked to keep up a druid tank on one of the council. I was able to do so successfully but I felt pressed against the backropes. It was extremely challenging and I knew that was partially due to my HoT build.
After that, I endeavored to work out a good hybrid spec that was equally good with single target healing as raid healing. The build above provides both but you do loose some out on the boosts that your HoTs would give. Note that I continue to emphasize haste and haste talents. That is very important I find no matter what you are doing.
I do want to talk about different strategies I tried. Essentially, I tested different things out and found that nothing changed anything I have said earlier about HoTing. Spamming rejuv is going to give you more mana problems and slower heals without the Tier 8 4 piece bonus. With each spell, I found that I could not find ways to use them without loosing HPS than what I described earlier.
I think the clincher for me really seeing the value in this build and not just seeing it as a slight nerf was on Anub,arak, the last boss of Trial of the Crusader. There are periods in there where tanks heavy constant damage. We were running with a pretty light healer group and I found that I needed to proactively spam nourish on the tanks or they would go down. Watching 13k crits go off and the tank go back to full really sold me on the value or this hybrid spec.