!WARNING! This is my opinion, not fact's. My english is not that good, so now u know :P
I started out in WOTLK playing as holy, and changed after a while to Discipline. I found it fun, preventing damage before it happends, place out shields before heavy aoe dmg, or a targeted area with aoe. Icc came, and people started whine'ing. And yes, I understand it, disc priests at the top of all meters, leading by far over second place. But you guy's that really complain about this, think over it. First of all, mana issue got a new meaning now, second, people started reacting a lot AFTER the buff was implented in Icc, becuase disc just flew over the roof. The reason for this was basicly that shieds were buffed with icc, so most of the aoe dmg was taken by absorb, without overhealing. The scale of 30% buff, shield and mana cost did not work all together at all. But we prevented the damage without overhealing all the time, but all the other healers would not have been so low on the healing if the disc priest wasn't there. Basiccly what I am saying is that most of the healing classes could spam heal in wotlk endgame, but since the priest got the Shield's, they become in many eye's overpowered. I am not saying that it wasn't, but then you was a true disc priest, preventing damage before it happend.
Cataclysm came, we all couldn't wait, and hell ye we /facepalme'd a lot because of the mana raise from wotlk, but we managed to adapt. I started out as disc, and IMO i was just like my lvl 80 priest, with less healing overall and a lot more mana issues. I felt the shields were broken, and disc were useless. Ye, most of us changed to holy for better overall healing. Patch notes came, disc was finally getting buffed, A LOT. I was as happy as never before, but it didnt last, hotfix, hotfix, hotfix. Shields cost more mana, but again you regain 1% more from rupture. My point is, for some reason changed blizzard everything with disc, and actually made the two healing speccs quite alike. Exeptions, CoH, Penance, grace, chakra.. and som minor stuff in our talent tree, you all know it, no point listing it all.
I really wonder what Blizz want with disc, because I cant find it as the same specc as I am used to, and love. From preventng damage, to do damage and heal. I cant complain about the grace fix, I love it, but all over it seems like blizzard is trying to make disc more like holy, with different spells. Yes, all healing classes got some threads you could pull together, but priests is again the only class with two healing tree's, and I really dont want them to be alike eachother.
Yes a lot of complains, but I got some small suggestion's to:
I dont want disc to be bubble spam, but I do want shields to be the most used spell as disc. What about limiting shields to a certain ammount, 2-3-4-5 shields at max out at the same time. reducing the mana cost a lot. Making it importen to keep out shields, so we got somthing to pat attention to, if even this seems to be healing to much, ill rather lower the mana cost and reduce the amount abosorbed than the other way arround.
Ill post more of my suggestion's when I get home from school, but feel free to comment and maybe some opinions of your own regarding changes that could be applied in later patches. I dont like the way disc is going, I dont want to bubbe spam, but I want t use shelds a lot.
and actually made the two healing speccs quite alike. Exeptions, CoH, Penance, grace, chakra.. and som minor stuff in our talent tree, you all know it, no point listing it all.
Now here you lost me. The two specs are quite alike, but you mention 4 out of plenty of differences between them...
Disc: Penance, Grace, Evangelism, Archangel, Atonement, Power Infusion, Pain Suppression, Train of Thought, Divine Aegis, PW: Barrier
Holy: Lightwell, Rapid Renewal, Serendipidity, Body and Soul, Chakra, Revelations, Circle of Healing, Guardian Spirit.
That's a total difference of 18 talents or abilities, and if with these you're gonna tell me that both builds are spamming GHeal and PoH, then I have a feeling you totally got it wrong my friend.
Edit: I played Disc as soon as they got efficient (start of wotlk), and stayed disc since. Only 3 days ago, I wanted to try out holy, and trust me I could not know how to play it well, and caused many wipes in the HC run from going oom.
As disc I use IF on every CD and spam GHeals to reduce its time, and still get some mana from rapture. As holy, I just couldn't find a way to regen my mana the way I did as Disc.
So no; I do not find their play style similar at all.