i must say all this is really stupid:
coh might seem overpower now to ppl, since all encounters are nerfed, and all encounters to sw geared players take 1-5 mins (at least for my guild, going mh 40 mins, bt 1.5hours and then sw 1 hour in one night).
so yes, with my gear i have 20% holy crit, 1535 spelpower unbuffed, and 12k mana pool. so yes i can spam coh like a "monkey" "bot" how ever you want to call it.
Yet, this doesn't mean coh is close to be overpowered: the mana cost of it is extremely high to the amount it heals. i don't know if you noticed, usually you take 2 CoH priests (called also "cross healing") atleast we do, and then CoH seems massively effective when 2 "spam" it. Yet with 1 CoH priest alone you will notice the amount of heal it does is really low compared to the high mana cost. CoH doesn't need a CD or a nerf to my veiw and i shall explain why:
if you have played on beta on a level 80 charr you would ignore this thread, naxx 10m and 25m the "raid healing" isn't like in sunwell (where encounters were build around "you need CoH"). From what i noticed from heroics 10ms, and 25ms, the main healing and my main attention went on tanks, the raid damage isn't a issue on most encounters, on most encounters you can leave a player with 50% hp trusting him to click the lightwell (which should be fixed, a dps needs to change his target to click it, same with a healer).
the other reason i believe it shouldn't get a CD is because its not a spamable spell: as in if the encounter is 2 mins, you can spam it cause you'll be oom when the encounter is over, yet for an encounter that will last more then 5-6 mins, i doubt you will see any priest spaming it. on the beta, when i raid healed, i usually CoH once with the prom jumping around and hoped for a SoL proc (which usually comes), to give the flash to the one that CoH didn't heal him, i open a lightwell and ppl just click it.
the final reason i think that coh doesn't need a nerf besides the fact that a priest will go oom if he stands and spams it. healing with CoH when its not needed, and not using the correct spell (for example coh a tank instead of a greater heal) usually finds himself guildless, or doesn't raid much, his healing might be on the top score of the beloved meter everyone looks and check. yet when you check spell usage and see 100% coh you know he didn't do anything to contribute much (or in other words a bad player).
i read a thread about twins: (holy nova + glyph + inervate = lol at twins).
for one holynova for one only heals your group, holy nova also costs almost same as PoH. While CoH isn't limited to your group. have fun spaming it though, don't forget your inervate call, holy nova spam is 30 secs -> oom, and thats really not the way to kill twins. i dont want to get into personal levels and asking you how many times you bombed the raid, i just assume you haven't tried healing with holy nova, you didn't read the tooltip and you missed it. i will also assume it was just a joke, and that you didn't do twins ever just like you didn't know holynova doesn't effect the whole raid only your party.
if you will spam CoH without combining Prom and the flash heal from SoL, to my veiw thats not a good player, and probably by spaming only coh is how to do it NOW when every thing is nerfed and easy. Yet, usually a piest that only spams his CoH button without combining other spells fails.
meters isn't the only thing ppl look at. in progressed guilds, coh spam doesn't work, in progressed encounters (which aren't terriably nerfed so kara geared ppl could see what sunwell is about) coh spam will not work. in progressed pve: coh spam never works, just like a shaman chain heal spam doesn't work, the heal needs to be smart:
the correct person with the correct heal. if the tank needs a greater heal, and you give him a flash heal you also fail.
to sum it up: coh doesn't need a nerf. it only seems like this because of all the encounters nerf so that all the ppl that didn't manage to get to BT and sunwell could manage to kill abit and see the end game encounters as well.