Oh the joys of people who make guides that offer no real information or, worse yet, incorrect information. Smidge about me, I've tanked most BC encounters and all Wrath encounters (including 3 Drake Sartharion) on my prot warrior and now doing the same on my new Frost Tank DK (3 prot warriors constantly raiding seems silly and DK DPS seems to be smacked in the head with stupid for jobs like death gripping sparks.) A couple of the gritty mechanics might be a bit outdated since I haven't crunched numbers in Wrath.
Threat and Aggro
First off, threat and aggro are generally discussed as separate things. There are two categories of threat, the innate threat that any ability has before healing/damage is taken into consideration, and the threat caused by damage and healing. Damage threat is damage dealt to the mob, and healing threat is healing done (not including overhealing) divided by two, then evenly divided amongst all mobs present (I'm 90% sure on this. Haven't raid healed since vanilla WoW). If you're within melee range, if you go over 110% of the current target's threat, you gain aggro. If you're outside of melee range, you need to go over 130% of the current target's threat to gain aggro.
The taunt mechanic is sometimes misunderstood as well. There's two bits to it. There's forcing the mob to attack you and there's gaining the threat of the current target. Deathgrip, mocking blow, etc. only force the mob to attack you, whereas the taunt effects, dark command and taunt, brings your threat up to the current target's threat AND forces the mob to attack you. So, if you're just making sure the mob attacks you while a mage meter humps, use mocking blow to establish it for a bit, let him hump, then taunt off right when mocking blow is done and open up some heavy threat.
Defense accomplishes several things at once. It reduces your chance to be hit, reduces your chance to be critically hit, increases your chance to block, dodge, and parry. To tank heroics and raids, you need to be uncrittable; druids are the only exception. Our furry friends are uncrittable out of the gate.
Defense is useless to druids. Stam stacking and agi stacking are far superior to any enchants/gems they can get.
Hit and Expertise
For a prot warrior, Expertise is *always* better than hit. No. You're wrong. Always better. If a raid boss can still parry (meaning you don't already have 60+ expertise skill), that -0.25% chance to the boss to parry you is still superior to +0.25% chance for you to hit. If you want the nitty gritty of why, check out some of my sites at the end of my post.
For paladins and DKs, you have spells as well, so it's a little less certain there. Still, aiming for the soft cap (-6.50%)is a good idea.
Right now, Deep wounds is the way to go. Really. It's *sick*. My deep wounds 25-man buffed are nearly 20% of my DPS. And remember, in defensive stance, DPS = ~135% threat.
Ignoring some of the basic must haves....
Imp Heroic Strike 3/3
Deep Wounds 3/3
Imp Thunder Clap 3/3
Why? Well, Thunder clap crits = deep wounds. 30% crit chance in raids means you can TC and put up deep wounds on most of your targets in fairly short order. Puncture isn't necessary with the rage we get now, especially since devastate isn't our most important skill anymore. And take anything that buffs your shield abilities.
Prot Warrior Priority
Yes, devastate is at the bottom of that. No, it really is. Devastate has the lowest threat out of all those abilities. Yes, it can proc sword and board, but rage is pretty easy to come by now and the others do a *lot* more threat and damage. I explain this to one of my fellow prot warriors and his DPS jumped up about 200 DPS, his threat jumped up at least 500 TPS if memory serves. And for the love of God, if you're above 50 rage, SPAM THAT HEROIC STRIKE! Spam it nice.
In short (lol?) you need a balance of experience and knowledge. One will never replace the other. I've seen amazing tanks that didn't know a couple key things and gimp their threat/damage output by 20%. I've seen "experienced" tanks telling newbies the completely *wrong* information. I've also seen tanks that really know their stuff to completely flop around on AoE pulls and panic the entire time.
Stay frosty. But take responsibility. If you die and subsequently the raid dies and you have one cooldown, one potion, one healthstone you didn't use? Your fault. Try harder next time
- Veneratio has a great blog here and it's very newbie friendly
- Conglomerate of great info, raid tactics and videos, forums with guides and the biggest tanks and theorycrafters out there - Ciderhelm and Satrina
- Theorycrafter paradise.
Any question, post away. Thanks for your time.