Back in the day of Yogg I had a special spec to Hit Gophers on the head Dispel the magic effects and diseases from the encounter
This allowed me to DPS as Shadow when I could, and especially in our learning stages be more mana efficient when doing the large volume of dispels that were required.
Blizz Blues have just announced changes to dispel mechanics to come into affect for Cataclysm
Which include
“We think the cost is too low…
“In Cataclysm we are raising the mana costs, making it possible to waste mana by casting a dispel when there is nothing to dispel, and removing Cleansing Totem, Abolish Disease, and Abolish Poison from the game. With these changes in mind, we are working to plan dungeon and raid encounters where dispels aren’t in constant demand or spammed in order to be successful, though some need for dispels will still be a part of the design.”
and
“Shadow priests won’t be able to remove disease in Shadowform”
So for the trade off – we get less encounters that require the attention to dispels that the Yogg encounter did – you can get penalised by wasting mana casting a dispel unnecessarily
and
Shadow Priests are going back to not being able to dispel disease which if you remember back that far. We have only been able to do since 3.08
I guess we should be grateful that we seem to be keeping Mass dispel – which remains unique ( at this point) to Priests. I am hoping that with this change to our class. That raid leaders will also evolve, and not require Shadow Priests to drop Shadow Form to Cure disease.
Blizz blues also said
“we are providing three dispel capabilities to all healing classes as follows:”
Note Healing classes. I shall interpret this as DPS ARE NOT MEANT TO DISPEL
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Pugnacious Priest's Warcraft Blog 
It’s a bit of a shame really. DPS classes certainly shouldn’t be relied on to dispel, however its the mark of a good “hybrid” that they can adapt to situations and react accordingly rather than simply tunnel vision whatever their role is.
As a protection paladin I often dispel myself to save healer GCDs, and will help out with other people if there are many people “infected” or the healer simply isn’t doing their job in a pug/weekly raid. In fact there are several situations where this has been part of the strategy, the most obvious one being tanking Steelbreaker and dispelling myself of Fusion Punch.
As a ret paladin as well, its common for me to dispel myself or others of poison/disease/magic if there are multiple people “infected” or if the healer is a little slow on removing that debuff that reduces my damage output or could kill me.
This is just another example of pigeon-holing players into specific roles that are being even further reduced in difficulty as the game gets easier and easier and provides even less distinction between good players and average players.
I agree with BAK, I feel “removing debuffs is the healer’s job” attitude is disgusting and even more disgusting when Blizzard is starting to support it.
And actually Mages are meant to retain their remove curse, so why not let shadow priests or ret paladins remove debuffs?
You could spot good dps now that he decursed, interrupted and used other utility instead of “just pew pewing to top the meter”. Removing the utility is sad, and looks like it’s another of “how pvp influences pve”, they don’t want dispel-dps teams. But hey, non dispelling classes like rogues and warriors already have an edge in pvp. Moonkins, dps shamans, shadow priests are under represented and usually told “your pvp spec is resto / disc”.
Sad, sad outcome.
Item the first: I approve of the concept of healy-style spells belonging to healy-style toons. My healer will be more than happy to break off healing the MT to dispel whatever some random foo picked up. NO PROBLEM. Tank wasn’t doing shiz anyway, didn’t need him.
Item the second: But, until that time, if one is DPS and has a dispel and I’m the RL, I’ll expect the one to use what was brought to the party, as needed.
My 2 coppers.
I’m feeling pretty pouty about this too. If anything, we need more classes that can dispel crap. I don’t mind it if healing classes have to dispel, I really don’t. But when one healer is needed JUST to dispel crap and nothing else, well that just sucks. That’s just too much boredom.
What about mages that can decurse? What about warlock pets nomnoming magic effects? I just freakin trained all the mages that they had better help out with the damn curses. I made husband download and config grid for it!
What happened to “bring the player, not the class”? I am fighting tooth and nail to make our healing team work no matter who signs up. We’ve had successful raids with 3 priest healers, or zero priests – the point is, this would make it so that healer diversity is a must, and DPS diversity is not.
Also… am I the only one that finds it REALLY hard to dispel crap off the boss while trying to heal? It’s not difficult at all when I’m DPSing, but when I’m healing, to try to focus on what debuffs are on the players AND what buffs are on the boss – ugh. I can’t brain that fast.
Zel, if it wasn’t clear, I do agree with your last paragraph there, especially when your MT healer has to spam for her life just to keep the MT up. Pausing to dispel can be disastrous.
Having SAID that, this is something that should be obvious during beta testing, if it even gets that far. If that’s the case, then healing / hots / tank toughness may be tweaked to adjust so that healers can also spare cycles to dispel.
I AM concerned that it might be too far along the design track at that point (beta) to correct things fully, if it DOES prove to be a problem. However, I know at least a couple of designers that are probably in the room when they have these discussions, and the following conversation surely took place.
“We’re gonna make healers do dispels too, and remove them from DPS.”
“Wait, my healer’s always too busy to dispel!”
“…” <– insert solution
Grimmtooth every indication is they want every heal to be a considered action in cata. The tank is @ 70/100k hp so I will now use my 20k heal, as such GCD”s are unlikely to be a problem.
Having said the disparity between. “Not all healers like doing dps so we wont build any dps to heal mechanics into the game” and “Your a healer, your going to be cleanse bot” like it or not, does stand out.