Today, I want to talk a bit more about my personal gear philosophy, specifically addressing what I find is a health pool which is much smaller than most tanks. My views on stamina seem to fly in the face of what I see preached on the forums, and even most other bloggers (who I find usually have an IQ higher than 37).
There are four things which I consider key factors on tanking gear, and two secondary items I also try to keep an eye on. In order of dicussions, these are Crit Reduction, Armor, Dodge/Agility, Stamina, Strength, and Hit/Expertise. The first four factors directly affect our ability to take hits, while the last pair are strictly related to our ability to dish out threat.
Crit Reduction: 2.6% crit reduction is ESSENTIAL TO TANKING. I repeat: Crit Immunity Is Not An Option (CIINAO, pronounced See Now). Last week, I saw one druid tank on the forums claiming he has tanked all the fights in the game a druid concievably can (Everything but Reliquary phase 2 and Illidan, if I remember correctly) without maintaining 2.6% crit reduction. And maybe he had. But the fact of the matter is, if you are crittable, you are a liability to the raid. Steady incoming DPS doesn't kill tanks, burst damage does, and crits are about as burst damage as it comes, especially if you get two in a row. You can get away with taking crits in normal 5-man instances. You can even probably get away with it in Karazhan and Heroics (In fact, I know you can, since I tank those in cat gear mostly nowadays). But for progression raiding, you would be sidelined if I knew you didn't have full crit immunity.
Armor: Due to our huge 5.5x modifier, armor is perhaps THE most important tanking stat for a druid. As I have mentioned in the past, it was the driving force behind all of my gear choices until I hit 29k armor (where crit heal armor buffs start first are able to push you to the cap against level 73 mobs, actually about 28,750ish). Even past that, I have valued armor on gear, though I have started to favor high armor gear with agi and stam on it over the higher armor with less stats type gear. As far as I'm concerned, other than that one (minor) turning point, the only diminishing return on armor happens at 35,880.
But why is armor so important? Well, in addition to the fact that we get so much more bang for our buck from it, the reason armor is so awesome is that it is so reliable. Armor reduces the damage of EVERY incoming physical hit, regardless of whether its an auto-attack, crushing blow, cri. . . right, we don't ever get critted, CIINAO and all. . .
Anyhow, armor is a constant, reliable source of mitigation, which leads to a more constant, reliable stream of incoming damage for the healers to deal with. And that makes the healers' jobs easier, as well as making it less likely they need to blow their cooldowns and expensive "Oh, sh**" buttons just to keep your fuzzy butt vertical (er, does it really count as vertical when you're tanking on all-fours? Bah, whatever).
Dodge: Once a bear tank starts wandering into the 30k+ armor club, mitigation upgrades start to show up more as increases to dodge than as increased armor mitigation. This is both a function of the gear we have available to us, and also the fact that there is in place a 75% mitigation crap . . . er, I mean cap,
There ARE some drawbacks to dodge, however, that are not there when it comes to armor. First of all, if you've ever run an instance a dozen or more times waiting for that one item with a 25% droprate to actually drop, you know how much the Random Number Generator (RNG) sucks. Relying on dodge to keep you alive is like betting your life that the Stranglestaff will drop on your next Kara run. Additionally, the more you dodge, the more likely the hits you DONT dodge are to be crushing blows. Note: I did not say dodge increases the frequency of crushing blows, I am simply pointing out that dodging more makes you take fewer regular hits, but does not reduce the frequency of crushing blows. A bear tank with 0% dodge takes 85% regular hits, 15% crushing blows, while a tank with 85% dodge would take nothing but the 15% of swings that would crush either way.
Because of this, I do not view dodge as a mitigation stat, per se. I instead view dodge as a way to help the healers with mana efficiency. Every time I dodge an attack, the healers have to pump fewer spells into me, and can cancel their casts, saving them the cost of their spell, and possibly even allowing them to enjoy some spirit regen outside of the 5-second rule. Ultimately, though, I imagine that if I never dodged an attack, it would be hard to keep me (or any other tank) standing even if the healers had infinite mana.
Stamina: Stamina, or more generally health pool, is perhaps the most simplistic, most basic tanking stat. The more health you have, the more damage it takes to kill you. Having a large health pool is critical to any tank, to be sure.
So why do I list it last in terms of mitigation? Well, I dont really, it actually has a value similar to that of defense and resilience. That is, if I dont have enough to reach uncrittability (enough stamina to survive long enough for the healers to get me back up), I need to do everything in my power to get enough, but if I DO already have enough crit reduction (stamina), stacking more is pointless. Yes, thats right, all those people who are constantly saying "Stick 12 stamina gems in ALL of your sockets, and enchant all of your gear with stamina enchants" are neglecting the simple fact that there is, in fact, such a thing as enough stamina. Sure, it never hurts to have more than you need, but frankly, if you never drop below 30% health, the truth is at least 1/5 of your health pool is superfluous, and you would do better pulling out some of those 12 stamina gems in favor of, say, 8 agility for some extra dodge, since stamina does NOTHING for your mitigation, it is merely a health buffer. As an added bonus, that extra agility will also make it less likely for your health to drop down as fast, so you may not even see yourself dipping lower!
That having been said, my unbuffed health pool currently sits between 13,600 and 14,400 health, depending on whether I'm using my pocketwatch or my Darkmoon card (which I tend to wear for tanking 25-man content). This is considerably smaller than what many tanks of my gear level run with, but I find that it is basically all I need. For the most part, I use agility gems in my gear instead of stamina gems, for two reasons. First, I have enough stamina (though I'm working on scrounging up a bit more at the moment, as I do seem to be drifting close to empty on the health bar more often than I like lately), and second, agility is a universal stat, used for both tanking and DPS. Not only does socketing agility let me NOT gimp my dual-use gear in terms of DPS, but it also lets me better fill the most common druid tanking role, that of an offtank who can DPS when not needed for tanking (add tank on Lurker, shaman tank on Maulgar, etcetera).
Strength: Honestly, I dont even pay attention to strength when it comes to my tanking gear. It IS an important tanking stat, giving us the attack power needed to generate threat, but pretty much any high-armor leather (that is, druid tanking gear) already has a bunch of strength on it, if only because that gear is hybrid cat/bear stuff. Dont ever add more strength to your gear, its not worth it (this goes for cat gear too, agility is always the better bet unless you cant get it on a particular piece).
Hit: Unlike Strength, hit is something that I actually actively factor into gearing choices, on the rare occasions I actually find a tanking piece with any on it. While also purely there for threat generation purposes (unless you stretch a bit and consider Idol of Terror needing Mangles to hit for it to proc), hitting reliably can be especially important in a couple of situations.
First of all, as of 2.3, hit rating affects warrior and druid taunts. And while not every fight is conducive to taunting, it is very bad news if your taunt resists at critical times (Such as Nalorakk transitions). Secondly, hitting is CRUCIAL when first engaging a mob. If your first 2-3 attacks all miss, you had better hope that the mob missed too, or your healers are likely to get a surprise when that first green number flies overhead. And even if you dont get hit either, its likely in that situation that your DPS is going to lay into the boss before you get a decent amount of threat, and they're going to eat the dust. Often times, this situation can be avoided by having hunters misdirect to the tank, but sometimes that just isn't an option, at least not for all tanks involved (trash pulls, Hydross transitions, High King Maulgar).
And if you're fortunate enough to be able to fit some expertise rating into your tanking gear, you dont just benefit by hitting more often. Expertise has the unique advantage of reducing a mob's chance to parry your attacks. And as you all (should) know, whenever a mob or player parrys an attack, their next autoattack comes SOONER. I have seen WWS reports before of a tank geting absolutely torn to shreds on Gruul when the melee DPS, cut off from Gruul's backside by a badly placed Cave-in, moved to the front arc where parrys occur, and Gruul getting something like 8 parrys in short order from all of those dual-wielders, each. Trust me, parrying attacks can be an INCREDIBLE boost to DPS, take that from someone who now has a prot pally who delights in fighting half a dozen mobs at a time.
So, to summarize: CIINAO, armor is a bear's best friend, Dodge helps healers conserve mana, it is possible to have enough stamina without fully socketing/enchanting for it, strength can be safely ignored given current itemization, and hit, while a secondary concern, can nonetheless be a big help if you can get it on tanking gear.