I though I had all the math figured out on what to wear for "DPS tanking" then a [Wildfury Greatstaff] dropped. I am assuming the additional FAP makes up for the loss of the FCR in terms of what you would use to DPS tank.

What would you use?

Favoring Wildfury over Earthwarden is probably one of the harder things I've had to reconcile, and not just for threat. Consider that fewer boss parry/threshes also reduce effective incoming damage. Of course, it's hard to quantify such gains.

For threat related situations, I like use Earthwarden on Hydross adds where snap aggro through lesser miss/dodge/parry is probably better for threat than a bit more FAP (although, Wildfury has gobs of Sta and Dodge which are also useful, but then Earthwarden has defense for crit immunity), and for my Magtheridon channeler so he doesn't get away at the start. Weapons are switchable in combat, so you've got a lot of flexibility in that regard, e.g. switch to your DPS weapon once Hydross adds are down and then switch back on the transition, switch to your mitigation weapon once Mag breaks free etc.

I've got a question which may be a little strange, but I believe this is the best place for it.

How long will these item comparisons matter?

Druids which wish to remain main-tank-capable are going to want the best of every slot. But I'm the 4th tank in most raids (2 prot warriors, 1 prot pally). I'm sitting comfortably above 30k/18k/40% or so in mostly tier 4. depending on the fight (typically w/o shout or imp). Does my max-mitigation gear need to improve to reasonably serve as the 4th tank on most fights?

My view is that Tier 5 isn't worth upgrading wholesale until you can get at least 3 pieces to break Tier 4's 4pc bonus. I don't know if I'll need those incremental upgrades. So-- when OTing, is there still stress on stam rating, or is it ideal in my position to push towards DPS enchants and gems in lieu of having "good enough" tanking gear?

Item comparisons will always matter as long there is a choice in what you can do in any particular slot, whether it's choosing between 2 items, or deciding what gems to put in it, whether to ignore the socket bonus, etc.

Spreadsheets and maths can only give a certain level of valuable input, much of the rest is situational and preferential. There are constant tradeoffs you need to make, sacrificing mitigation for avoidance, or avoidance for stamina. Ideally, one needs to evaluate one's "main" role in their raid (MT, 2nd MT but some DPS, mostly dps but some OT, only DPS) and gear accordingly.

You've said you are the 4th tank on most raids. Your gear choices should reflect that. Agility is a great stat for that, as it nets you a good amount of dodge and crit (avoidance and threat for Bear) whilst simultaneously allowing you switch to cat once your channeler is dead (for example) and still put that agility to good use (AP and crit for cat).

2T4 is ridiculously good for DPS, and 4T4 isn't worth breaking for tanking until you get ~3T5 where the sheer stats will start to outweigh the 4T4 bonus. But in your role, you're still better off gemming pure agility, using CE enchant over KoT, DPS shoulder enchant over the tanking one, and then making up crit immunity in other ways (KoT exalted trinket, PvP bracers/belt etc, there are many options) if and when needed. Stamina is probably not good value in your role as you will get "enough" from raid buffs.

Again, a lot of these decisions are highly situational based on exactly what you do in your raids.

This is essentially the root of my question. Does the 4th tank get put in situations where they need MT-like mitigation in Hyjal and beyond (Like Alar, VR, and the shaman on Karathress do now)? You make some statement about gear which have been made already in this thread, but what wasn't here was-- is every fight going to be a compromise? Note that we generally do use our warriors and pallies to tank in any situations we wouldn't gain an advantage using a feral.

-edit: removed a redundancy.

There is no fight in Hyjal or BT which requires more than 3 tanks (except council, but in that case the 4th tank is a mage). In fact, Karathress is the only fight I can think of which requires more than 3 tanks, if you ignore caster tanks (maulgar/leo/council/illidan). A fourth tank is useful for trash, but will never be in an MT or OT role on a boss, iirc.

Thanks Dukes, that's exactly the answer I was looking for.

Unless you are consistently swapping around players in your raid, using a feral druid as third or maybe even another as second tank is very useful. While some fights actually require 3 Tanks, there are others which only need one or two. While a third protection warrior will be almost useless there, a feral druid can still output a lot of dps.

Aye, that's our reasoning pretty much. We don't swap around alot of players mid raids so I just switch to the roll the fight requires, be it dps or tank (or even heal).

Posted a very detailed description of Rawr's rating system at WoW Forums -> Theorycrafting: Method for Rating Bear Gear

Hydross, Alar and Kael are the fights we also use a 4th tank on. On Hyjal trash it is very useful to bring a 4th tank and as thats more of a pain than all but the Archimonde bossfight in there, not having it available is doable but not desirable in my opinion.

I guess you can do Hydross with only one add tank or at this point let the free maintank grab the first add. Alar p2 adds can be tanked by a dps warrior aswell. We learned Kael with 4 tanks to get more control over the fight, i guess that aswell can be done with some relearning and reworking of the tactic with 3 tanks.

The same you could say about Karathress aswell tho. I tanked the healer already as a moonkin and im guessing a dps warrior in tanking gear has no problems after you entered BT even if he only took leftover items.

However i see a problem here because you will want to bring the 4th real tank for learning those encounters, but then in BT you dont have much use for him anymore. The best solution would be a good dps warrior/druid who doesnt mind respeccing alot while learning the encounters.

3 tanks on 25 people was a good change for BT, but messes a bit with guild setups. I hope they keep it for the next 25 man instance.