Healing Theory, Part 5: Haste

Previous posts in this series can be found here. In particular, the Haste section of Part 2 might be useful background.

Haste is the most complex of the healing stats, and often appears to be the least well understood. Its effect is a combination of added throughput, increased mana consumption, and increased HoT healing due to those “haste breakpoints” that are so easy to look up online but so hard to evaluate in importance. Part 2 in this series, linked above, gave some high-level comments on the behavior of haste, and generally concluded that based on its basic function, it’s likely to be unattractive. I said that I would dig into its effects on a class-by-class basis in the future, and that is what I’m doing in this post.

Incidentally, this post is written from a patch 5.4 perspective. Among various other things, haste will have no effect on the RPPM proc rate of the legendary meta (and legendary cloak), greatly simplifying the analysis.

Concepts

First, a slightly different framework for how haste effects the two main categories of spells. We’ll refer to this throughout the post.

1) Non-HoTs. Haste does not increase the healing per cast (HPC), nor therefore, the healing per mana (HPM). It increases the healing per cast time (HPCT) by 1% every 425 rating. It is worth pointing out for comparison that a typical mastery, like Druid, Holy Priest, or Paladin, increases all of these metrics (HPC, HPM and HPCT) by 1% per 480 rating. In general even from a pure HPCT (spam throughput) perspective, haste tends to be only slightly ahead of stats that increase your healing on a per-cast basis.

2) HoTs. Haste now increases the HPC. An important point I want to press on: in the long run, haste still increases the HPC by 1% per 425 rating. The “haste breakpoint” (HBP) phenomenon means that that increase to HPC comes in clumps, but the average gain is unchanged. Especially late in the expansion when the difference between a high-haste and low-haste build may be 20000 rating, it’s this overall scaling pattern that generally determines the relative attractiveness of the two. HBPs tell you what haste points to “snap” to in your reforging, but generally don’t control the overall value of haste. The only general exception is the first non-automatic HBP for any important spell, which requires a smaller investment to reach.

Haste2

What about the HPCT of HoTs? After all, if the HPC of HoTs increases, and the cast time comes down, the HPCT should increase like the square of haste. Here is the second important point: nearly all important HoTs have cooldowns or other mechanisms that prevent this. Wild GrowthHealing RainRenewing MistRiptideHealing Stream Totem, and Sanctuary have cooldowns. Rejuvenation and Renew have fixed 1-second GCDs. Lifebloom and Efflorescence are persistent and only allow one concurrent instance. The only notable cases where haste increases both the tick count of a HoT and the frequency with which it can be applied are Eternal Flame (tricky, see Paladin section below), Glyphed Riptide, and Tree of Life.

Summarizing: Haste increases HPC for HoTs but not for other spells. Non-haste stats increase HPC for all spells. Haste increases HPCT for (generally) all spells, but so do non-haste stats, and haste rarely gives a double benefit, so this factor is close to being a wash. Also, HPC is the more important metric than HPCT since firstly, mana is a relevant factor to healing, and secondly, many (most) important spells have cooldowns and cannot be spammed.

The key factor then in evaluating haste for any class is the portion of its total output that consists of HoTs. If a class gets 20% of its output from HoTs, there is essentially no way to justify spending rating to increase that portion of your healing by 1% per 425 rating, instead of increasing all your healing by 1% per 480 rating (or a similar amount depending on the class and stat in question). If a class gets 90% of its healing from HoTs, then in the long run, increasing that 90% by 1% per 425 rating is likely to be the strongest stat allocation.

Since most of the classes wind up with a little more nuance to the analysis that this, I’m going to move through them one at a time, rather than simply posting some WoL breakdowns and being done.

Disc Priest

I’m going to start with an easy one. Disc has the DoT component of Holy Fire and that’s all (ignoring an occasional Renew, if that). The DoT is about 1/6 of Holy Fire, which is itself a few percent of Disc healing. With only a negligible portion of heals having their per-cast strength improved by haste, the attraction of haste for this spec is nil.

One related issue: haste lets you cast more Prayers of Healing during the 10-second duration of Spirit Shell. But of course, what matters isn’t the number of casts you apply, but the total amount of Shell shielding applied. Mastery is nearly as strong as haste for this, doesn’t cost extra mana every Shell, and actually gives a benefit during the other 50 seconds of every minute. So there’s nothing here strongly favoring high amounts of haste. Under the principle that a first HBP is usually efficient, you might make sure to have enough haste to cast 5 Prayers of Healing during 10 seconds. But with the T16 set bonus and if you start Shell with Borrowed Time up, this is only 2116 haste (with some leeway for latency since this isn’t a true HBP).

Haste does theoretically increase your number of Smite casts in a fight, which saves a half-second of Penance cooldown here and there (frequently amounting to nothing if you’re on GCD when the Penance cooldown finishes). Again, nothing approaching a meaningful reason to use the stat.

Conclusion: gear for minimum possible haste.

Holy Priest

RenewSanctuary, and Lightwell Renew. It’s something, but by no means a predominant majority of healing done. A skim of a few top logs shows less than 20% of healing from these spells typically (it tends to be slightly higher in 10-man where Renew/Cascade/Serenity builds are more likely). Not much to add here. It’s simply not enough to make a stat attractive when it adds HPC to this small a portion of your heals, while other stats add slightly smaller percentages to all your heals.

As usual, you can tweak around low breakpoints a little. Your first Renew tick at 3039 (4721 if glyphed) is essentially a free large bump to Renew since you can’t dip your haste much below it anyway (this is what I said above about first breakpoints of important spells generally being good to pick up). Beyond that, 4717 for a 1/3 increase to Lightwell Renew might be worthwhile if Lightwell reaches around 10% of your healing, but this is dubious.

Conclusion: gear to minimum haste, but not below 3039.

Shaman

Now we’re getting somewhere. Healing RainHealing Stream TotemRiptideEarthliving, and Healing Tide Totem (although you might argue that raid cooldowns are best ignored for this purpose). The exact breakdown varies due to content, but over 80% is very common (or even 90% in some 25p encounters), with more Healing Rain at a stationary fight like Megaera, and more HST at spread mobile fight like Primordius. It’s easier to look at it inversely and see that it improves essentially all significant heals except Chain Heal and Greater Healing Wave, which tend to be a small percentage in 25p and higher (often 20-30%) in 10p. When looking at Shaman breakdowns, remember to exclude Restorative MistsAncestral Guidance, and Ancestral Awakening from the tally.

So we don’t have a clear conclusion yet, and my purpose here is more to discuss the mechanics and see where the value of haste is than to completely solve Shaman gearing. Also, more detailed log studies will be better conducted after 5.4 due to the huge buffs incoming to Chain Heal, Healing Rain, and Healing Stream. The above somewhat suggests that you should favor a high-haste build in 25p, and that 10p will be closer. This is all complicated by Shamans’ strong crit and mastery bonuses as well (not to mention Spirit in 25p due to Mana Tide).

Assuming for the moment you do conclude that haste is strong due to a very high usage of the spells listed above, you then do have to consider HBPs. The goal is to pick a level that picks up big chunks of healing on important spells, to minimize the extent to which haste is wasted by ending between HBPs on other spells This does mean that some of the value of haste is always lost at the top end, since the last few points aren’t benefiting all relevant spells. In this case, the 8 ticks of Healing Rain (HR-8) HBP is at 50%, and Healing Stream-11 is at 46.7%. This makes 50% (15316 rating with Ancestral Swiftness) a good stopping point, without another good one until HR-9 at 70% haste, unlikely to be practical or efficient even in better gear. Aside: Healing Stream HBPs are not precise since they depend on the latency of when the totem disappears, so don’t gear exactly to them.

Conclusion: pending 5.4 log analysis, but in general, if using a significant ratio of Chain Heal and other non-HoTs, minimum haste since other stats are better. If output is dominated by haste-favored spells, consider going up to HR-8 unless Spirit stacking for Mana Tide in 25p.

Druid

The HoT class, although as we’ve seen, that moniker is just as apt for Shaman. Haste adds healing to each cast of RejuvenationWild Growth and to the small HoT components of Regrowth and Tranquility. In addition it smoothly improves the tick rate of the omnipresent Lifebloom and Efflorescence (in 5.4). In the non-haste column is healing done by Swiftmend, heals cast with Nature’s Swiftness and the T16 2-piece, and Wild Mushroom non-bonus healing (Mushrooms will charge faster from stronger Rejuvs, but this is irrelevant unless you usually use them before full charge).

The situation is very similar to Shaman, in that the HoT portion is in the ballpark of 80-90%. And again, it’s hard to pin down right now since spells on both sides of the line (Efflorescence and Wild Mushroom) are getting improvements that, while not as dramatic as the Shaman ones, will cause them to do more healing. I’m going to be revisiting this more on EJ since Druid is my native class, but where I’m leaning right now is that making Efflorescence, Rejuvenation, and Wild Growth stronger is generally more important than making Wild Mushroom non-bonus healing and Tranquility stronger. Rejuvenation is actually just about dead even on haste vs. mastery since the instant tick doesn’t benefit from haste, but both the T15 4-piece and T16 2-piece bonuses make the extra tick a better way to deliver the heal. Small soft factors push towards haste as well–increased Clearcasting procs, shorter GCDs on many instants adding a small amount of convenience, better use of Tree of Life, and a better proc rate on some trinkets.

As to HBPs (emphasizing again that we first look at the overall value of haste, then worry about finding a convenient stopping point): Haste without Rejuvenation is a nonstarter. This is exactly why Resto Druids ignored haste in MoP until just now when the Rejuv-6 HBP at 13163 is coming into reach (those middling HBPs for Wild Growth or SotF were never particularly efficient). Rejuv-7 isn’t until 23262 rating and may not be practical even in this tier.

Conclusion: 13163. However it’s only a small benefit over the familiar 3043 Rejuv/Tranq-5 HBP, and the latter may be more convenient depending on gear. Stay at one of the two to avoid wasting stats.

Monk

Back into simpler territory. The only important HoT in this toolkit is Renewing Mist. And while it’s a lot of healing, it’s not over 40% or so (Monks would start liking haste at a lower HoT threshold than other healers since it’s 50% stronger due to Stance). Moreover, their fixed 1 second GCD means that haste’s benefit to HPCT is much more limited than usual, and haste does nothing for some spells. In particular this includes Soothing Mist: due to a quirk of the way the channeling is implemented, spamming the button every GCD allows you to get exactly 2 ticks per second regardless of haste.

So the conclusion is simply going to be to always sit at the lowest convenient Renewing Mist HBP. The conclusion would be to absolutely get down to the lowest possible HBP, but Monks have the unfortunate situation of not liking Spirit or mastery either, so you may not find it to be worth the trouble to shuffle those stats around after maximing crit however you can. Again, the goal here isn’t to write a guide for each class but to discuss the benefits and limitations of haste.

An added complication of Monk healing makes it especially important to reforge to some HBP: you care not only about healing output of Renewing Mist, but also the duration, since that affects your ability to Uplift more targets. Duration of a HoT is highest just after a HBP, when it is half a tick longer than the listed duration, and steadily declines until the next HBP. Dayani at Healiocentric discussed this at length for Monks here (and she also helped me with research for this post). There are lower-order effects where higher haste HBPs slightly reduce total Renewing Mist duration, but slightly speed up the jumps to new targets, shortening or lengthening Uplift windows by fractions of a second in either case. For our purposes here, the important conclusions are that you do not want to have any extraneous haste beyond an RM HBP, but being at higher ones is not especially helpful.

Conclusion: any low haste breakpoint, after you’ve shifted all possible stats to crit. The lowest few are 3145 (RM-11), 6151 (RM-12), and 9158 (RM-13).

Paladin

Before Sanctity of Battle included Holy Shock, what this would come down to is the amount of healing accomplished by the HoT portion of Eternal Flame (including its effects on Beacon of Light and Illuminated Healing). Suffice to say, it was not high enough to justify haste on its own. But let’s put that aside for a moment, since things are lot more complicated now

Sanctity, in brief, reverses the usual function of haste. Its benefit is that it allows the Paladin to use cheap Holy Power generators more often, thereby displacing some portion of more expensive spammable generators that would otherwise be used. The key fact is that the only benefit to all this is efficiency. The biggest problem haste runs into, then, is that the best alternative to the Sanctity-affected spells is Holy Radiance, not an especially inefficient spell. A stat whose principal function is to displace Holy Radiances from your rotation has a big hill to climb in making itself attractive. To be clear, getting to cast Holy Shock more often is still better (that’s why you use Shock on cooldown). The problem comes up when you talk about paying for that privilege with a heavy investment into a stat.

Without building a full-blown Paladin model in a spreadsheet or describing one here, an efficiency-based comparison is therefore a good approach for a simple evaluation. Let’s start with 5.4 Selfless Healer setups.

With no haste, you can cast 10 Holy Shocks and 10 Judgments per minute, as well as 3.33 free buffed Radiances. What happens if you invest into 10% haste (4250 rating)? Now you get 1 extra of each, plus 1/3 of a buffed Radiance. All in all the haste has given you the opportunity to spend 28% base mana to get 2.33 HP, plus the healing done by one Holy Shock, 0.53 Radiances, and 0.33 Daybreaks. Without the haste, 2.33 HP would have cost you 2.33 Radiances, or 84% mana, and I’d also have gotten the healing done by those 2.33 Radiances and 2.33 Daybreaks. The latter option costs more mana (specifically, 56% of base, or 33600 more) and does more healing. To see which is better, realize that instead of 4250 haste rating, I could have taken 4250 Spirit, which gives me 37370 mana in 1 minute (taking Divine Plea into account). So haste, in the end, has saved me less mana than Spirit would have, and caused me to do substantially less healing (as 1.8 Radiances and 2 Daybreaks is far more healing than one Holy Shock).

Eternal Flame builds make this trickier, as haste now provides both a benefit from Sanctity, and a boost to the Eternal Flame HoT. The Sanctity benefit is much smaller than before, since now it doesn’t even give you the extra HP or special buffed Radiance. All you’d get from that 10% haste is 1 more Holy Shock per minute, saving you 20% mana compared to getting that HP from a Radiance (equivalent of 1000 MP5), but doing less healing.

We now have to finally revisit our usual analysis of seeing how much healing is done by the Eternal Flame HoT. This is hard to estimate in logs due to Illuminated Healing and Beacon, but on paper, a Holy Shock+EF pair does 37% of its healing with the HoT, and a Radiance+EF pair does 23%. 30% overall is a fine estimate for now. This by itself, going by the logic throughout the post, would not be enough to justify haste based on the HoT effect. The proper comparison of heals affected by haste to heals affected by mastery would be 30:70, not 30:100, since mastery doesn’t affect the HoT, but that’s still not enough. Let’s even assume that instead of comparing, say 4250 haste to 4250 mastery (8.8% mastery), we siphon off 1400 points into Spirit to account for the 1000 MP5 mentioned in the prior paragraph. Mastery being 1/3 weaker even still doesn’t make the comparison attractive for haste. It looks something like 30:50 now in terms of weighting, analogous to a class that did 60% of its healing with HoTs. But not only does that still make haste subpar, but there’s the value of the extra Holy Radiances in the Spirit/mastery build that we never took into account.

Conclusion (a surprising one, I think): minimum possible haste. If using Eternal Flame, keep the EF-13 HBP at 3506.

Summary

The following healers should avoid haste rating beyond minimal HBPs, if any: Priests, Paladins using Selfless Healer, and Monks.

The following healers get some reasonable value from haste, but barring more detailed models, it appears to be weaker than other stats: Paladins using Eternal Flame, and Shamans who aren’t fully AoE healing.

The following healers get enough value from haste that it is likely advantageous over other stats, but not drastically and only when set to efficient HBPs: Shamans who are fully AoE healing, and Druids.