Hey, I’m just perplexed by the current stat distributions that were settled on for tank sims. I’ve tested these manually in-game keys from 10-12s even with large pulls and I’m mythic raiding. I’ll start as an example of guardian druid Best-in-Slot for mostly/all TUF. It wants almost ZERO versatility which makes little sense. Even shifting the damage taken to a lot of magic damage it has only minimal amounts of versatility distribution. It wants mastery and crit primary. I do understand the dodge factor and damage increases from crit. And that mastery increases maximum hp and healing received. And I also know that the crit and mastery buff can double dip. Also, Protection Warrior does something similar but instead of crit which would allow parry chance it goes for mastery haste. I know you rarely want mastery on Protection Warrior for damage or damage reduction. The all-dps route for both tanks is much more similar to what you’d see in stat distributions for DPS increase and mitigation, while both seem a little heavy in crit weight but other than that it is a fair distribution. I’d love some explanation here and why it is doing these things. Especially mastery on warrior is extremely shocking because good warriors in M+ have nearly 100% uptime on shield block which gives a 100% block chance. So outside of critical block, there would be zero reason to take mastery as it loses out in almost every other way to the other 3 stats.
So one spec at a time:
Guardian
I think your main question can be simplified to this: why choose Mastery for toughness over Versatility for a Guardian Druid?
The short answer is that I just think it’s better.
Longer answer: Mastery and Versatility serve a pretty similar purpose: they both reduce the magnitude of incoming damage relative to your maximum health, but they do it in different ways: Mastery makes my health pool bigger, and Versatility makes the incoming hit smaller.
If your main concern is reducing the size of big hits relative to your health pool, Mastery is vastly superior. We can illustrate this with a simple example.
For easy math, say that I have 10 million health and I am taking a hit for 5 million damage when everything else is said and done (e.g. your armor, etc.), and I have zero extra Mastery and Versatility. This hit will do 50% of my max health as damage.
Now let’s add a budget-equivalent amount of Mastery and Versatility, and see how much each changes the result.
Case 1: Add 7000 Mastery rating
This is equivalent to 10 mastery points (every 700 rating gives 1 mastery point). You have a base mastery of 8 points, so we need to factor that in when doing this calculation.
One point of mastery increases your max health and healing received by 0.7% – this can be extracted from the game spell data or verified on your character sheet in-game.
Original health (with just base mastery):
10m = h * (1 + 8 * 0.007)
h = 9.47m
Health with an extra 7000 mastery rating:
H = 9.47m * (1 + (8 + 10) * 0.007)
H = 10.66m
Percent of max health taken by the hit:
5m / 10.66m = 46.9%
Case 2: Add 7000 Versatility rating
Every 1560 Versatility rating = 1% damage reduction. So 7000 Versatility rating would be:
7000 / 1560 = 4.487% damage reduction
Now we can calculate how much the hit will do:
D = 5m * (1 - 0.04487)
D = 4.78m
Percent of max health taken by the hit:
4.78m / 10m = 47.8%
Comparison
So Mastery reduced this hit to 46.9% of our max health, and Versatility reduced it to 47.8%. Another way to state this is that Mastery gave us a 3.1% reduction, and an equivalent amount of Versatility gave us a 2.2% reduction.
From this perspective, Mastery is roughly 40% more efficient per point on gear for reducing the size of hits relative to our max health.
Other Concerns
Reducing the size of hits relative to your max health is not the only concern when tanking, though it is probably the most important one for increasing your toughness in hard content.
Versatility is sometimes preferred because it reduces your total damage taken and thus reduces the amount of healing required. This has typically given it and other damage reduction effects an edge over methods that increase maximum health.
Guardian Mastery was designed to fix that problem – as it increases your health pool, it also scales up healing received proportionally, which keeps the load on your healers constant.
It is always possible that I’m missing something, but I can’t really think of a realistic situation where Versatility would ever be preferable to Mastery for toughness on a Guardian. Except…
Damage
Most tanking advice you see out there is heavily weighted towards tank DPS. That’s fine – in a lot of cases tank damage is meaningful (Mythic+) and you can get “tough enough” by using one of the less-efficient toughness stats that is better for damage (like Versatility).
As you noted, if you move the slider closer to a DPS strategy on our site, it will indeed drop most Mastery and favor Versatility more heavily. This is more in line with what you might find elsewhere because that is how they are gearing: heavily skewed to damage.
Doesn’t change the fact that Mastery is better for toughness, it just represents a community preference for damage that we encourage you to follow if you also prefer it!
I’ll make another post about warriors later when I get some time to look at it in more detail.
Protection Warrior
For protection warrior I found a bug! It was definitely pumping up Mastery a bit too high, and we’ll fix that in the next site update.
It had to do with the armor constant that is used to apply diminishing returns to the amount blocked by your shield. We were using values that we found during beta, but they changed a bit when TWW went live. The value changes depending on what content you are doing (e.g. a Mythic raid diminishes your armor and block value more than a Normal raid), and it can be a bit tricky to find the correct value, especially for Mythic+.
So once we update that, Versatility is a better defensive stat than Mastery for protection warriors in most cases. The only time Mastery would pull ahead is if a very high percentage of your damage taken can be blocked (about 80% or more), or you can’t maintain high shield block uptime for some reason (rare).
Similar to Druid though, to get the kind of stat distributions that you’ll see on most other sites, you need to put the slider closer to the damage side, e.g. set it at “Mostly DPS”. As mentioned in the druid post above, most sources heavily favor gearing for damage. That’s a totally fine thing to do (as long as you are staying alive), so please do so if that is how you like to gear!
We are one of the few sources that will give you a mostly defensive gearing option if that is how you like to play, and it will look different than other suggestions you find out there.
So I mostly agree with the mastery/versatility differences for guardians. I have some opinions on the two stats due to double dipping and exterior interactions. But, I was not directly comparing your recommendations to other sources in the traditional sense. I do a lot of theory-crafting and custom apl creation myself and just was pointing out a few things based on those. I think AMR is the best defensive sim out there for tanks.
Out of curiosity, to which particular double-dipping and exterior interaction effects are you referring?
Also, we did post the update with the fix for Protection Warriors, so that should be straightened out now.
The mastery benefit of the additional healing (as far as I can tell) also scales with vers. It is scaled from both since it acts as an ability of healing, which is like leech for healers. It still works for them as they get healing from the heals they do. Or, like with shielding, it is nice to have vers usually over mastery. If you’d like to talk more about tank/sims for tanks I joined your disc and am willing to talk there I can’t check the forum as often.