Why block rating is a good stat for paladin tanks?
Block Rating the Tankadin stat
A paladin needs 67 % (with heroic libram) or 72 % (without heroic libram) total block/dodge/parry/miss (depending if they value their libram) to be uncrushable with holy shield up. Doing this significantly reduces damage taken from boss mobs and in some cases because holy shield has 8 charges could be seen more effective at reducing burst damage than a warriors 2 charge shield block (This is an opinion of mine feel free to keep your own).
Blocking = Threat generation
As many of you will know a paladin blocks and reflects holy damage. This damage does 2.5x the damage in threat. Dodge/parry and miss will push block chance off the combat table if I am not mistaken. So upping those stats is not beneficial to your tankadin.
Why block rating?
It is very, very cheap. 32 block rating 4.02 in a trinket slot vs. 32 defense rating (2.13% avoidance) VS 38 dodge rating (2%). it is clear that with block rating you can gain the avoidance stats without pushing block chance off the combat table. It will also make the damage intake more stable by allowing you to focus on stamina/armor and block value gear. For paladins having an 8 charge holy shield is a blessing there is no need to keep charges active and rather to spend them and be able to take more damage. This fits well with the 'trash tank' usage and 'main tank' usage.
So go all out to get block rating?
No, no, no. Get the good pieces of avoidance gear as well but there are excellent items like [item]Iron Gauntlets of the Maiden[/item] and [item]justicar shoulderguards[/item] that are accessible early on ([item]crystalforge shoulderguards[/item] are better for effective health as a 1to1 comparison). However by getting block rating in these slots you can focus easier on stamina and armor, without having a negative effect on your healers/group/survivability/threat.
It is about balance.
Yes it is keeping 102.4% total avoidance is the most important thing for a paladin tank who intends to sometimes tank bosses/trash that can crush. However going for high block rating items allows you to gain stamina. For instance if I changed to the maiden gauntlets and justicar shoulderguards id lose gain 2 stamina (over my potential current set up) but id also gain 34 block rating which is potentially enough to gain 45 stamina on a trinket slot!
But I want an oh shit button
Well if you want you can use Moroes pocket watch however chances of it being what saves you are slim, rather a constant 500 hp than a chance that you might not die or even a block value trinket for trash.
Armor isn't important, is it?
Well considering you are reading this, Iíd think you would know that it is. Lets put it in simple terms: I had roughly 12.5k armor when I started Karazhan and I paid Doomwalker (I like soloing raid bosses /flex) I got 1 shot by a crushing har har forgot to buff holy shield >D I had about 12.8k hp though my combat log showed me only getting hit for about 12k. So that is about 8k normal hits and now when I paid him a visit (I get bored fast) he was only hitting for 6.5k~. I was at 15.3k armor then. The difference was I had more block value and armor 2.8k more and had gained 1.5k hp~. Now thatís impressive stuff when you think of armor as a 2:1 ratio meaning that 375 armor cloak is worth 18 sta? Thatís incredible!!! So what if my numbers are off? Well even if they are less and a 3:1 ratio that 375 armor cloak is still worth 10 sta!
Is a fairly nice passive talent that reduces all damage taken by 30% when below 35% hp. It has 2 flaws though; firstly being below 35% is not a good thing and secondly it can be leapfrogged. Armor and stamina do increase the effective range of this. I can't do the maths I am going to admit that now, However do consider this talent if you are able to stack armor and stamina and remain uncrushable. It may save you. Paladins can get up to 20khp fully buffed in SSC/TK level stuff. That means the range of this talent is at 7000hp well most bosses are hitting at 3-5k so its safe to say the chances of being hit into this range and not being bypassed are high, also it means you could potentially survive a 5k hit at 5k hp just some food for thought. This talent is great for AoE tanking and decent for boss tanking. Well for me anyways I can give a poor example. I was below 35% hp and Gruul silenced me (the poor part is holy shield was not up) so I got crushed and died however would I have died had I not been crushed? probably not since it was mitigated by 30% and became a 5k crushing would have been a 3k normal hit at this time I must have been below 5.9k hp so at 2.5k hp it would have killed me but thatís a gap of 3400hp, chances are the talent would have saved me if not for the poor mechanics of the fight.
Block Rating is a very cheap stat that can potentially be used to increase the amount of gear slots you can spend on more important stats e.g. stamina, armor, block value and spell damage (though mostly that is limited to weapon). It also means you are more likely to block than not increasing the effectiveness of holy shield.
You are free to make your own opinions of the stat and its value but it -is- the easiest way to retain uncrushable and get more stamina on gear for a paladin. Using tankpoints you can work out if such up, down, sidegrades are worth it. if your health raises alot and you can retain uncrushable its generally a good thing. I tank heroics with 14k unbuffed hp and have done most with 1 CC including underbog and SH, i die much less now eventhough i have significantly less avoidance! due to mechanics my hp is only 13.5k hp for raid tanking =).
Discussion is welcome, correcting my poor maths is welcome and criticism is welcome :D i have no problems with being wrong, I am only human I am supposed to make mistakes :rolleyes: