Ellyh

Actually I talked to a senior lecturer in statistics I know at the university I used to work at and he worked out a couple of simplified cases for us.

According to his calculations and assuming a simplified situation of spamming greater heal (cast time 2.5 seconds) and a boss swing speed of 1.5 seconds (averaged over specials and regular hits) we get the following cases

For a 25% crit rate and a 50% avoidance rate the probability of overwriting a Aegis is a whopping 23%

for a more realistic 20% crit rate and 40% avoidance rate we get a still substantial 17% overwrite chance.

This is higher than either of us calculated as he calculated the full odds including the fact that there is an exponential probability distribution around the time to the event.

We don't need to calculate the probability of the initial state occurring as we are interested in the conditional probability of a second event conditional upon the first event happening. The probability of the first event occurring is completely irrelevant just as if a series of coin flips the preceding flips are irrelevant to what happens moving forward.

 

Kortar

Grace certainly does. But Divine Aegis really doesn't. To understand why, imagine for a moment you had a 26th player in your raid who did nothing but toss Flash Heals at random intervals on the tank. Would this help? Not really. Sure, there's a minute chance that one of those random micro-heals would actually save the tank from dying. But most of the time it would just be a waste because the heals are unsynchronized with either the other healers or the boss' damage. Divine Aegis is better than having a straight 195% critical effect bonus. But it doesn't magically make random happenstance a solid strategy for healing.

The only way to reach a better understanding is via debate. If everyone is just saying "wow! Shiny new talents!", you don't really learn anything about just how shiny those talents are. In terms of healing a raid - I also posted comments on Paladins and Resto Druids - everything needs to be taken in the context of what other healers are also doing, so you need to understand how every healers works in order to play any healer.

 

Kopalec

Except your analogy isn't valid. Divine Aegis doesn't work like a 26th healer randomly casting Flash Heals. It places a Shield on the tank that lasts for a duration of time, increasing it's chances of being there when it is needed. Also in the cases that it is not needed, going by Ellyh's numbers above, a 17%-23% overheal rate is comparitively rather low to other heals.

 

Ana

Penance can also crit heal on individual bolts and I have had DA overwritten by back to back penance crits. Although since individual bolts of penance are fairly small, the shields were also negligible.

 

Ellyh

More importantly can a tiddly little 500 point penance Aegis overwrite a 4000 point greater heal Aegis? If it does it makes the timing of penance a more complex decision as you don't want to use it shortly after a gh crit (on the same tank).

 

Kopalec

If past experience holds true, then yes the smaller DA proc will overwrite the larger. (similar to Blessed Recovery talent) As to the chance of that occuring? Haven't done the math, but whatever it is...........there is an equal chance that the next Greater Heal will overwrite the Penance DA proc.

 

Kortar

Think about it for a moment and you'll grasp why this makes no sense. If you heal damage in the present, this is not worse than healing damage in the future. The damage you healed in the present is still healed in the future.

The only real benefit to the shield methodology is that it temporarily raises effective tank maximum health. So in the case where a burst for more than the tank's maximum health but less than maximum health + 30% of crit just so happens to coincide with that critical heal, you're better off.

In essence, Divine Aegis is just a gimpier version of Inspiration for the purposes of raid healing.

 

Zaroua

Seems like you're contradicting yourself there.

But really, the only viable way to look at Divine Aegis (unless they dump healing Priests' crit rate to absurd levels) is as an extra anti-tank gib mechanic. If you picked up Divine Aegis, it means you're missing a lot of the deeper Holy talents that greatly increase the benefits of the two spells that would make Divine Aegis shine on raid healing: Prayer of Healing and Greater Heal. It also means that the Discipline Priest won't be picked to be the "raid healer" in raid situations over Holy Priests/Resto Druids/Resto Shamans and maybe Holy Paladins if they make BoL worth casting - in AoE situations a Discipline Priest wouldn't be very effective with or without Divine Aegis. If someone wants to cook up the numbers of using Prayer of Healing with Divine Aegis Vs. PW:S spam in AoE situations, feel free.
But keep in mind that right now, the tree looks like it has a higher focus towards healing between one to three targets by keeping Grace up and making good use of Rapture/Borrowed Time and the other PW:S talents.

If a Druid specs Moonkin in Darnassus, do the trainers still laugh at him?

 

Kortar

I wasn't very clear. By 'raid healing', I was really referring to 'healing in a 25-man raid', not the specific task of healing non-tanks.

That being said, the actual heals received by Holy Priests make them much better at tank healing. With the exception of a minimal number of casts to stack Grace, every time you want to cast a heal on a tank, you'd prefer it came from your Holy Priest - superior longevity, larger/faster heals, etc. On the other hand, where Discipline Priests really excel is in covering bursts on non-tanks via Power Word: Shield. Weakened Soul makes it impractical to depend on PW:S for tanks, but when you're switching targets every 4s anyway, Weakened Soul isn't a significant drawback.

In terms of more subtle roles, it would be tough for Discipline Priests to compete with Paladins for single target healing or Druids for a small cycle of healing targets. Essentially, everywhere you look, there is someone better at the job you'd ascribe to Discipline Priests (and, in most cases, they're at best third behind Holy Priests) with one exception: the use of PW:S.

Unfortunately, the build that makes sense to me - a hybrid dps/healer that uses PW:S as its primary heal while spending most of the time on dps - doesn't crunch well. It's simply too far behind the curve dps-wise and depends too heavily on widespread raid damage pounding up against those Reflective Shields.

 

Tainter

I really don't see why Blizzard doesn't finally fix Blessed Recovery (and DA of course) to not have smaller benefits overwriting bigger benefits. For HoTs and DoTs it works just fine. I question wether the current state is intended or wether they simply forgot to fix it sometime along the path.

If they can't sort it out then maybe DA and BR should be made a fixed percentage of the HPs of the affected player and let it stack. Nobody likes broken talents.

What I currently dislike is the heavy focus on PW:S in Disc. There are 23 or so talents that affect PW:S now. That's a bit too much for my taste and spells like Inner Fire, Mana Burn and Dispel Magic should really get a bit of talent love. I'm still not entirely convinced by Penance either. It seems to be too situational in PvP and maybe not good enough for PvE.

If you can't join them?
Beat them.

 

Kopalec

Divine Aegis allows the Disc Priest to heal in the present (GH etc.) and the future. (Shield proc) It allows the priest to make use of what would normally simply be overheal. Your analogous 26th healer would be only minorly effective as their FH would need to land at precisely the correct moment. Divine Aegis's duration improves on that drastically by sticking around until it's needed.

Yes, the proc does raise effective max health, and the situation you describe would be the anti-gib benefit it provides. That is not the only use for it however. It also smooths out the damage taken over the duration of the fight. This allows the possibility for anyone healing the target to down rank or stay outside the 5sr if so desired. It could even prevent another healer, say a raid healer, from needing to jump in to help out. This would mean less sacrificing of your Dps while trying to save your MT.

As to DA being a gimpier Inspiration, I believe that would be dependent on the size of the proc. I haven't done the math to determine the effective mitigation of a large shield from GH, vs. Inspiration. It's mostly irrelevant though, as DA isn't mutually exclusive to Inspiration, it's "in addition to". Thus making a Disc priest's critical heals "the best" in game.

 

Slyness

I was under the impression that Blessed Recovery was fixed and it only overwrites larger crits. I haven't tested it myself but I read something along those lines in the Arena Junkies forums.

 

vesicular

DA will help mitigate all damage. Inspiration only helps to reduce physical damage. And, like someone else said, you get both.

I think it's obvious holy will have the better throughput, but it's also more reactive. Disc is more passive "healing", and if the new talents for all classes are any indication, tanks will need some help evening out the damage spikes, which Disc surely provides.

 

Tainter

I never read anything about it in any patch notes. When I get back home on Thursday I might just test it.

If you can't join them?
Beat them.

 

Lambi

Yes this is if you heal like a calculator/robot or forgot to turn your screen on. I can guarantee you that for a good priest you won't have more than 10% overwrite, probably around 5%.

 

Ana

Smaller crits do in fact overwrite the shield from prior larger ones. I submitted it as a bug, but I'm not certain if it's intended or not.

 

constantius

You can't guarantee that at all. It's hyperbole. Either back it up with statistics, or explain the methodology you are proposing to use in your healing rotation to ensure that it doesn't happen.

Stupidity cannot be cured with money, or through education, or by legislation. Stupidity is not a sin, the victim can't help being stupid. - R.A. Heinlein

Anyone who cannot cope with mathematics is not fully human. At best he is a tolerable subhuman who has learned to wear shoes, bathe, and not make messes in the house. - R.A. Heinlein

 

Incoherence

At the risk of piling on, what new insight are you bringing that is going to prevent a "good" priest from overwriting his own shield without stopping healing entirely (which is probably a bad idea for the kinds of bosses where Divine Aegis is helpful)? I suppose you're going to say that stopcasting should take care of that (because you would cancel a heal which would land into a shield and therefore into a full health or nearly full health tank), but stopcasting is really something you'd rather avoid doing on a hard-hitting boss (anyone remember doing Malchezaar near BC release and canceling a heal right before a thrash hit-hit-crush?).

Hm, actually, looking at those numbers again, I hadn't noticed before that the overwrite effect means that Divine Aegis gets a slight diminishing return from more crit (more crit = more chance to overwrite the shield)... the more I look at it, the more I find to dislike about it.

 

Kopalec

See, statements like this, I just don't understand.

Your talking about a new game mechanic that lets you use something that mostly goes unused in live. As of now crit heals are of only any real use due to Inspiration. The added heal size from the crit however just goes to waste as overheal. Now all of a sudden Divine Aegis comes along and says, "hey, wanna put all that overheal to good use?", and replying, "No not really. I like wasting the extra healing."

The 17%-23% overwrite of the shields is only very loosely termed "overheal". It is taking what was most likely all overheal and giving it a purpose. It's not something to complain about that your crit portion of heals are being made more efficient, just because it's not 100% more efficient. Seriously, ever heard the term "looking a gift horse in the mouth"?

One last thing as well. I tried to point it out more subtly up thread in reply to Ellyh, but the overwrite chance will work in your favor just as much as it works against you.

 

Ellyh

Totally, it's an effect of how the whole thing is set up. A high overwrite chance is actually a good thing on those hard hitting fights because it represents an increase in the probability of the shield being up for any given swing. A very low overwrite chance is generally bad as that represents a high likelihood of an unshielded hit or thrash going through. However at the same time the total average combined equivalent healing throughput from the disc priest goes down because he is getting less that 100% throughput from his Aegis.

The real determiner of Disc healing viability will depend on how all the changes to block and general tanking mechanics works out. They are significantly changing the whole tanking model with regards to block and threat generation. The latter moving to an AP based threat scalar will significantly change the way tank value stats and produce knock on effects on mitigation and avoidance. Reports on the beta warrior forum suggest that current raid itemisation is very bad for threat generation and a more AP oriented build makes holding aggro far easier. How these 5 man experiences translate from 5 mans to 10 man and 25 man raiding is still the big unknown in the whole picture.

On another topic PWS is only a viable raid heal on those fights that have sustained raid damage to the raid member(s). This is because PWS is not a "Heal" but a temporary damage reduction. It is only useful in those fights where you can pretty much guarantee that the healee is going to take close to the full value of the shield in the next 30 secs. Thus fights like Kaelecgos and Gorefiend it is a good choice as it effectively identical to a heal. Fights like Council or Supremis it will be bad as these are single time random events where a direct heal is highly desirable because the damage is not sustained.

PWS as a viable raid heal will ultimately depend on the design of raid encounters. Sustained raid damage fights will favour it while random spike raid damage will highly disfavour it. My personal wild ass guess based on the CoH, Druid AoE cooldowns and general blizzard commentary is that they will be moving more to the latter model for raid damage.

 

Incoherence

Divine Aegis rewards a higher crit rate than is needed to keep up Inspiration. In fact, it's linear with crit (except for the overwrite chance). So this leads to two questions:
1. Is Divine Aegis enough incentive to look for crit above, say, the 15% you'll probably end up with naturally?
2. If not, is it worth taking anyway?

For question 1, Divine Aegis can be considered a 45% crit modifier on heals (on top of the current modifier, which while nice when it happens is largely negligible, so we'll call it 50% total). So 1% crit would increase your HPS by 0.5%. Using current values, that means that spell crit is roughly 1/3 as valuable as haste as a HPS modifier. (1% haste increases throughput by 1%... mostly. Spell haste is about 2/3 as expensive as spell crit.) As a shield, it has the obvious benefit of a temporary increase in tank HP, but at some point you ask whether it's worth the drop in throughput. My remark about overwrite chance means that this calculation is actually somewhat optimistic: due to overwrites, some of those shields will likewise be "wasted", so the effective crit modifier is less.

For question 2, probably. Even at 15% crit, Divine Aegis is a 6.75% increase in HPS for 3 talent points, which isn't too shabby (especially because your alternatives aren't particularly compelling either: Imp Inner Fire? Imp Renew?).

 

Lambi

I didn't think it would be necessary to explain that any good priest won't be casting 2.5 second greater heals back to back when the tank has full hp, inspiration and a divine aegis on him. You'd use the gcd on a pw:shield/PoM/renew for the tank instead of chain casting gheal non stop. Especially since disc priests get mana refunds on pw:shield you'll try to use it as much as you possibly can.

Take sentinel tank healing on M'uru as your prime example and you'll notice you're not even close to crit healing or even normally healing a full hp tank that often.