I've been using a strategy of haste > mastery > crit for gear selection, reforging and enchanting, but I'm coming back to this character after a little bit of downtime and reviewing that in light of statements made in this guide. So I spent an hour or so playing with SimC. Running sims with my existing gear it says increasing my mastery would be better than increasing my haste. My current haste:mastery ratio is is about 2.3:1. If I change my enchanting and reforging strategy to try to equalize my haste and mastery, SimC shows me a very small but detectable decline in DPS. If I try only dropping my reforges where I have reforged mastery into haste, I can't find any difference at all (any gain or loss is completely lost within the margin of error).

Furthermore, it would seem to me that haste would have "real life" advantages that mastery probably does not. As far as I'm aware, mastery is not capable of proc'ing clear-casting (does anyone know if it can proc trinkets/power torrent?). And more importantly, you will not get a mastery proc from a spell cast that you cancel (either to interrupt or to move), but you will get back into the fight faster with more haste.

If someone could demonstrate a situation where reforging haste to mastery actually yields a significant gain in DPS, I would be very interested to see it.

The take-away from all of this appears (in my novice opinion) to be that we shouldn't neglect gear upgrades that may have mastery in place of haste, but that it's very likely best to stick with the haste > mastery > crit prioritization for gemming and enchanting.

So, you're saying that if I have 1 charge of clearcasting and cast Lava Burst, then the mastery proc will gain the +10% damage buff even if it's no longer present when the proc'd spell is casted? And that if I gain clearcasting after I cast Lava Burst (maybe my prior LB crits or the LvB crit) the mastery proc will not be effected by the +10% damage buff?

This suggests that the mastery proc inherits the character attributes present at the time of casting Lava Burst when it automatically casts the proc'd 75% damage spell. So it doesn't make sense that Unleash Flame has no effect on its damage, but that clearcasting has the stated effect. Does elemental mastery effect the damage if it is present for the cast of Lava Burst, but not when the proc is casted?

It doesn't really make sense that the glyph doesn't effect mastery procs, but it could easily be designed to function that way.

Ah, I'm sorry. I need to stop posting at 5am. Most of what I said still holds true, but I'd like to edit Clearcasting...

The mastery proc is affected by Clearcasting, but contrary to my before statement, it is calculated separately from the initial cast. A stack must be present while the mastery proc is firing, and the mastery proc is not affected by the initial cast's crit and buff. ie: Cast Lava Burst with one stack of Clearcasting, no buff. Cast Lava Burst with two stacks of Clearcasting, buff. If you do not take the Clearcasting talent, it will deal the same damage as the Lava Burst with one stack did (confirming that there's no buff).

The rest of my post still stands, though. And if I did not say it, I did not test it (or get any results). At your suggestion, I did attempt Elemental Mastery in the same fashion, but... well, on a ~1.5min timer it's a pain to do. I'll try again later after I've eaten and woken up, but for right now, no answer.

This fits with what I had thought the model was before: mastery procs a separate cast that is calculated independently at the time the auto cast occurs. Unleash Flame clearly wouldn't have an effect on the proc. In that case, it's probably not worth the effort to try to get a mastery proc as EM is expiring, because it doesn't really matter (we're going to cast LvB/LB/CL whether it does or doesn't effect procs). If you want to check something, it would be great to check the 4% lightning glyph on mastery procs. If that glyph effects mastery damage of LB but LvB glyph doesn't effect LvB mastery, that might make a difference in how you glyph for various fights. I suspect that it will function like the LvB glyph, but it shouldn't be difficult to check.

There is some wonkiness in the Mastery 75% math.

Don't hate me for conjecture. I don't normally test this stuff. I just play.

But in ZG the giant ogre/troll things that create the purple void zone that causes double dmg, I noticed hitting a 104k Lava Burst which produced a 44k Mastery Overload.

Had Clearcasting and Unleashed Elements up, the LvB glyph, and the ogre/troll was in the 100% void zone for both hits.

The casted and mastery LBs are different spells with different spellids (403 and 45284 according to wowhead). The glyphs probably apply only specifically to the spellid carried by the casted spell. According to wowhead's list of things that modify the spells, no talents or glyphs buff the mastery proc for LB, but talents buff the LvB proc (not the glyph though).

I understand that and agree (for the most part), but if you look at stat plots similar to the one we get for haste and mastery, you will frequently find that there are "break points" where one stat passes the other, even though they may cross back and forth repeatedly, and the likelihood that I am sitting exactly at one of those is very low. This is to say that in all likelihood, the inverse of what would be gained per point is very close.

Furthermore, if two stats provide equal benefits it is likely that stacking one to an extreme at the expense of the other will yield worse results than balancing them, because there is a synergy between them (more haste = more casts to proc mastery or crits, and vice versa, more mastery = more procs from faster casts). This is what masanbol means when he says, "so generally speaking you do not want to stack one over the other." However, I have not found that to be the case in my own testing with SimC. Even though I am currently stacked highly in favor of haste, moving to balance with mastery results in only nil or negative results. If we assume these stats to have equal value, I can imagine circumstances where having haste would be better than having mastery (say when cancelling a cast to interrupt) but I can't seem to think of any where a mastery proc would be of greater benefit than haste.

I'm mostly interested in being proven wrong, because if someone has a case where balancing mastery or increasing mastery instead of haste actually yields a significantly positive result, it means I need to revise my strategy here.

I don't know if you guys saw this in the Enh thread, but it's an interesting mechanic that does indeed work. Does ele incorporate it into their TC models? Enh will likely start using a LvB_FS_UE priority item or something of the sort.

If you don't feel like reading, or for people skimming, if you chaincast LvB into FS with the UE buff up, both spells will benefit.

As mentioned in that thread, this mechanic has been known for a while to resto shaman abusing it for gaining an "extra" buffed Riptide after another spell is cast under UE. The problem with making use of it as Elemental is that UE itself was only ever something that was cast while moving because it's a DPS loss for elemental regardless of what it buffs. Obviously if you did end up using it due to shocks and Spiritwalker's Grace being on cooldown, the LvB+FS combo was a good use of the buff. However, with the addition of Glyph of Unleashed Lightning, we're not scraping around for things to do while moving anymore.

I believe this to be incorrect. My understanding is that UE becomes a minor DPS gain over LB filler when (and only when) it can be used to buff both both LvB and FS. However, the gain is very minor and does not justify re-applying FS early and would be entirely lost if you messed up the timing and, say, the LvB cast finished after the existing FS expired (or a variety of other scenarios). Delaying a LvB cast at all in order to use this trick is also likely a DPS loss. Thus this "trick" is only useful (at least to elemental) when a large set of conditions are met (FS needs to be reapplied, UE is off-cooldown, LvB is about to come off cooldown but is not yet available, et cetera).

However, it's true that some of the justification for not using this was that UE was one of the only things we could do while moving and that's no longer true with the new glyph. I do substitute UE for LB when all of the stars align properly for it, but if I have any doubt about being able to successfully pull it off without disruption to my normal rotation, I simply don't do it. It is at best a very minor DPS increase, and you're better off focusing on the core rotation mechanics until you have them very near perfect, which is no longer a trivial feat with the FS/ES conflict.

This is probably very late and most of you likely already know it, but I've been meaning to post it here for a couple weeks.

As elemental AoE is very clumsy for Beth'tilac, I've taken to going upstairs on the fight and I found that planting my fire elemental totem there leaves the totem up across two phases (until the totem expires). I am not absolutely certain that the elemental is able to attack during the "downtime" but I think it does and it's at least active as soon as she's re-engaged. She does not appear to damage the elemental prior to being re-engaged by a player. This would also work for restoration shamans, if you wanted to send them up to heal the first phase they could drop their elemental totem and leave it there.