Tonight I spent a half an hour playing with Rejuv, Lifebloom, haste and crit trinkets, and Button (tossing totems on her shaman alt) and we’ve made some discoveries regarding HoTs and DoTs and how they’re updated. Though I didn’t record exact numbers, I’ll try to explain our methodology as clearly as possible so skeptics can replicate it. This is SCIENCE after all, gotta have replicability! Oh look, I think I just made up a word. Yay me.
The TL;DR crowd can scroll past this section and just see the results.
First I tried casting Rejuvenation and Lifebloom with and without the benefit of Ephemeral Snowflake‘s on-use effect. I would cast the spell unbuffed several times, try to get a feel for how long there was between ticks, and then use the Snowflake partway through, and then refresh the HoT a few times while the buff was still active and try to get a feel for that. When it expired, I would watch and judge for a few more refreshes. Later I took advantage of Button’s Bloodlust to see a bigger change in haste rating at work. Lifebloom ticks too fast for me to judge with, I feel, any degree of accuracy, but I could tell a real difference with Rejuvenation (especially with Bloodlust up) and it very much seemed to me that Rejuvenation did not update in real time, only when the spell is overwritten. However, the tooltip that appears when you mouseover the buff updates in real time, meaning that it doesn’t necessarily reflect the actual rate at which the buff is ticking.
Then I tried more or less the same thing with Nevermelting Ice Crystal ‘s on-use effect. I repeated this a number of times, but the randomness of crits, combined with the relatively short duration of modern HoTs, made judging anything difficult. I am quite certain, however, that refreshing Lifebloom with Empowered Touch does not let it keep the Ice Crystal’s buff to crit indefinitely (which is consistent with blue posts, but cue disappointed “awww” anyway).
Next I tested spellpower with the help of Button’s Searing Totem. Spellpower is very straightforward to track since it gives nice, consistent changes to the numbers your spells spit out. Again, I tried both spells with and without the totem up, tried refreshing Lifebloom with Nourish, and in this case we experimented with Efflorescence too. These spells definitely do not update with spellpower in real time, but neither does refreshing Lifebloom extend the benefit of any spellpower buffs that have worn off.
Button did some similar tests with her shaman spells. She tested Flame Shock, Riptide, and Healing Stream Totem, and our friend Blanket tested Renew on his priest. Of them all, only Healing Stream Totem updated in real time, and that only for spellpower – the totem isn’t affected by haste at all. Also of note is that she found that Flame Shock’s DoT (and, I would assume, the direct damage portion of the spell as well) is subject to the caster’s spellpower at the time the spell lands, not at the time it’s cast.
In a nutshell: The effect of spellpower on HoTs and DoTs definitely does not update in real time, only when refreshed or overwritten. Haste likewise seems to update only when refreshed or overwritten, though we lacked the tools to measure it quantitatively. The tooltips of the buffs do update in real time, which makes them inaccurate. The only exception we’ve found so far is Healing Stream Totem, which is continuously updated. Most likely, the effects of crit don’t update in real time either, but our testing of that is inconclusive. For spells with travel times, the effects of the caster’s stats are calculated when the spell lands, not when it’s cast.
In other news:
Tree of Life and Empowered Touch
This may have been obvious to other druids, but I didn’t realize the potential to do this until Button pointed it out to me. There IS a workaround to the thing that’s been bothering me most about druid tank healing in 4.0.x – that is, the ability to put Lifebloom on only one person at a time. Although they both update spellpower and haste the same way now and people often use the two terms interchangeably, refreshing a HoT is still a different mechanic from overwriting it. None of it made any difference to we of a leafy persuasion before because we had no means to refresh HoTs, but now, with Empowered Touch, we do. And we also have a reason to: Refreshing Lifebloom on someone does not remove the triple-stack of Lifebloom goodness that might be ticking away on anyone else, even if Tree of Life form has worn off!
This means that you can, in theory, juggle Lifebloom indefinitely on both tanks. It doesn’t sound easy; at feasible levels of haste it takes two seconds to cast Nourish and Lifebloom has a ten-second duration. Since lag can screw with your timing and you want to be extra sure to keep that hard-to-replace HoT-pile from falling off, you’ll probably want to refresh it at least a second early, giving you an effective duration more like nine seconds. So you’ll be forced to spend about 4/9 of your time, or 44%, just keeping Lifebloom up and ticking on both tanks (though at least you’re still getting Nourish’s healing out of it too). Is this an exploit? Maybe. Is this worth the effort? I’m not sure, but I’m looking forward to giving it a try.