(I wrote in depth about the combat table in a previous column. If my bar napkin explanation is lacking, I definitely recommend reading that piece first.)
When you're starting out as a fresh 85, this isn't a problem. You just don't have enough dodge, parry, or block to reach that height. However, after you start raiding, it won't be long before ilevel scaling takes over and the higher numbers of mastery and avoidance stats allow you to accumulate that stack. It's inevitable.
And on top of that, unlike avoidance stats, block doesn't suffer from diminishing returns. It's impossible to ever hit the kind of avoidance levels we saw at the end of The Burning Crusade. It is not impossible to accumulate an equal amount of block chance, as there's never any point where adding more block becomes prohibitive. Up to the cap. Which is another issue in of itself.
This wasn't a big deal in earlier expansions, where blocking was for small hits and trash. With the dawn of Cataclysm, though, the stat got a new lease on life. Suddenly, it could remove 30% of the damage from any physical hit that was block. Overnight (with the release of 4.0), it became our best stat.
That's the ultimate problem with block chance. Because of the lack of diminishing returns and because of its potency as you accumulate more and more of it, it exaggerates the poor design of the one-roll combat table. There is only the inevitability of capping when one is allowed to increase (with no diminishment) a value in a static, limited system. There can be no other outcome.
Let's step back from the mechanics and talk a bit about the visuals. Just at its face, the block chance mastery is invariably disappointing. Here is a stat -- block chance -- that existed in the game up until 4.0 and was removed because block was considered either boring or broken (with the verdict oscillating back and forth, seemingly dependent on what time of day it was), yet instead of being completed wiped from the face of Azeroth as one might expect after being so derided, it was repackaged with a shiny, new bow and forced upon the two shield tank classes as mastery.
Mastery! The glimmering new stat that was supposed to be the hallmark of class design in Cataclysm! Other people in our raid are sending shadowy clones of themselves at the boss or (let's be more generic) getting some additional X every time they do Y; we get the returned and renamed stat which was stamped as fit for deleting.
And you thought it was insulting that they took the pre-nerf version of one of our abilities and gave it to us as a four-piece tier bonus.
In addition, not only do we have the laziest mastery design in the game, we also have the only mastery that has a hard cap. Once we have 102.4% avoidance plus block chance, any further mastery itemization we add onto our pile is completely wasted. All the additional block chance we place on top of that tumbles right off along with normal hits and crits.
At least warriors get an additional value from every point of mastery they add above the soft cap of total combat table coverage. I'm not saying it's optimal to go beyond that, but considering how easy it is for us to reach total CTC and how hard it is for them to do the same, you'd think it'd make sense for the situations to be reversed and paladins to get a little something else from our mastery, to keep the stat somewhat worthwhile after 102.4%.
The sleeping giant
The biggest sin of our mastery and of the block mechanic in general is how dangerous it is to balance in the final analysis.
When patch 4.0 hit during the waning days of Wrath, we were told that it was OK with paladins to have a block chance mastery paired with an amazing new incarnation of block, because no way, no how would they ever be able to cap. Diminishing returns? Oh no, not needed. The numbers just wouldn't be there.
Never mind that at the end of Wrath, the introduction of reforging in 4.0 allowed raiding tanks to block cap for their final weeks in Icecrown Citadel.
But even before that, back in the Cataclysm beta, someone on the official tanking forum ran the numbers on the gear available in 5-man heroics and saw that it was already possible (admittedly with some heavy stacking) to block cap as a paladin. And that's before even collecting raiding gear. In response, Blizzard nerfed the mastery, reducing how much block chance we'd get per point as well as the base block chance from the mastery, but as a consolation, upped the value of a successful block to 40% damage reduction (with the old, passive Holy Shield activated). This was the version that made it to launch.
That was the first and last time Blizzard would attempt to rein in block in Cataclysm.
Then throughout 4.2, we played the Will They or Won't They? game as Damocles' Nerf Sword dangled above out heads. Finally, Blizzard announced it wasn't happy with the idea of paladins block capping, but it wasn't going to bother to fix it in 4.2 because there wasn't time to deal with the potential balance fallout.
And again, 4.3 rolls around -- and not only are paladins block capping, but warriors are, too (thanks again to the immutable flow of scaling over time). Paladins are shedding mastery left and right, as the stat has become a nuisance even to those of us in normal modes. Sure, it made for a fun minigame to balance our stats, but there is something deeply wrong with how low level the shrugging off of mastery is these days.
Now, at the last tier of the expansion, mastery is akin to hit chance for a DPS player, something you cap and then spend an inordinate amount of time cursing under your breath every time you are burdened with more of it, as you must find a way to not lose any itemization.
Ultimately, even with the rollback in stats incoming with a new expansion, this isn't exactly a sustainable environment. Mists of Pandaria needs to do something radical to the protection paladin mastery to keep it balanced, keep it interesting, and keep it from once again being a ticking time bomb. Block chance is too powerful (and yet, paradoxically, too boring) a stat for us to put all our eggs into its basket. It's time for a change and to correct the horrible design mistake that has hung around our necks since Deathwing first tore the world asunder.
The Light and How to Swing It shows paladin tanks how to take on the dark times brought by Cataclysm. Try out our 4 tips for upping your combat table coverage, find out how to increase threat without sacrificing survivability, and learn how to manage the latest version of Holy Shield.