In order to have the perfect balance of hit rating and expertise, we need to have gear that gives enough of it, but not so much that we have more than we know what to do with. A few egregious examples of how this isn't always easy to do come with this very raid tier.
Fabled Feather of Ji-Kun is a huge front runner for best strength trinket of the tier. This is because it has a strength proc that provides massive amounts of strength quite often. The normal raid drop level feather provides a whopping 4.31% hit. This is more than half of what any strength DPS really needs, since almost everyone, even dual wielders, considers 7.5% their cap, and that's just on one trinket. Our full normal tier 15 set provides 5.16% hit, which means our set and our feather alone result in around 1% hit over the cap. Pair that up with various +hit gear in other slots, and you're looking at so much hit, it'll be actively difficult to reforge it all away. For example, if you're using Zerat, Malakk's Soulburning Greatsword, that's another 3% hit right there. Mind you, all of these issues are magnified if you're using thunderforged or heroic gear, which will have even more hit rating to go with their higher item levels.
Now, admittedly, part of the mitigating factor here is meant to be that you won't necessarily have the exact combination of gear to be stuck with too much hit rating, but not only is it very possible, there's a lot of best in slot gear that has unusual amounts of hit rating. The possibility, if nothing else, is something that is not unusual and at some level, hard to avoid for someone who is dedicated to raiding Throne of Thunder every week.
Reforging: The problematic solution
Even if you do have too much hit rating, it's not a big deal, you might say. After all, reforging isn't that hard to get done, is it? While reforging helps, it has some problems of its own. First, of course, is that reforging can only be done in small chunks, so you'll probably have to juggle multiple reforges at once, trying to calculate exactly which reforges to use in which order in order to get both hit and expertise rating to as close to the caps as possible without going too far under and order. Of course, in theory you can get around this in part by using a website or program like Ask Mr. Robot. Of course, even Ask Mr. Robot can't hit caps exactly if the math doesn't work.
This is arguably a problem unique to hit and expertise. Certainly, haste plateaus can be a problem too, but even if you go slightly over a haste break point, that extra haste rating isn't completely wasted, in theory. With hit and expertise rating, it very much is wasted.
The other thing to consider about reforging is that it was never really intended for the use it's currently put to. It was originally touted as a way to allow gear to be used by a wider array of classes by letting them reforge away useless or near-useless stats. Instead, it's become another min-max tool, and rather than allowing customization, there's always an optimal, mathematical "best" way to reforge.
So how do we solve this?
Interestingly enough, it appears even the devs are noticing that hit rating and expertise aren't necessarily contributing to compelling game play. Ghostcrawler's even said in tweets that they've toyed with removing then completely. Is that the direction we're heading? It's certainly possible, and Blizzard is making a similar huge step in patch 5.3 with the PvP resilience changes. That said, it's possible it might oversimplify gear, and as with the shield block changes, and even the presence fixes, Blizzard's shown a tendency to revamp things rather than remove them or oversimplify them. So if not removing quickly, how could Blizzard fix things?
One possibility might be to simply raise the hit and expertise caps to a point where they could never reasonably be reached. This means that they could fit into a reasonable gearing scheme wherein they'd fit among haste, mastery, and everything else, but you wouldn't feel pressured to hit an exact cap. The downside here is that missing an Obliterate 3 or 4 times in a row could get incredibly frustrating.
Another possibility might be to create some extra side benefit to hit and expertise past the cap. The idea here is that it gives some benefit, so if you have to settle for having a bit of hit or expertise past the cap, you don't feel like you've got dead stats on your hand. The challenge would be balancing it so that whatever the extra effect is, it doesn't overshadow or duplicate other secondary stats. Adding a chance to inflict some extra damage seems like a possibility, but it might come too close to duplicating critical strike chance, for example.
Whatever the solution, tackling the problems with hit and expertise seems like it may be one of the more prominent of Blizzard's overarching balance challenges. We probably won't see extensive changes to it in the middle of an expansion, but patch 6.0 may be the perfect time to address a set of stats that just don't really feel engaging or fun anymore.
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