The problem with hit and expertise as stats in World of Warcraft
is fairly simple: they do the same thing in practice, even if not in theory. The more hit you have up to the cap (i.e. the amount of hit needed to hit a skull level mob, which is effectively level 93 in Mists of Pandaria
content since we're raiding at level 90) the less likely your attacks are to miss their target. This means that not only will they successfully deal their damage, but you'll properly generate the resources said attack would generate (if any), hold threat (if that's what you're doing) and so on. Similarly, the more expertise you have up to the soft cap (the amount of expertise needed to ensure that an attack from behind a skull level mob will not be dodged) the less likely that your attacks will be dodged, which means they're more likely to successfully deal their damage, generate resources, hold threat and so on.
Expertise' only real difference is that it also reduces the chance your attacks will be parried, at a much higher cost (the parry hard cap being almost twice the dodge soft cap) but, again, that just means that expertise does the same thing as hit twice
. Since warriors don't need to worry about ranged attacks for the most part, we can be grateful that at least we don't really need to worry about spell hit caps
and factoring both hit and expertise into spell hit chances. Since expertise caps out dodge chance and only then
parry chance, it just becomes a very complicated
means to determine whether or not your attacks do damage. In the end, while there's plenty of mechanical difference between hit and expertise, they do
the same basic thing. The purpose to these stats is to give you something you can cap to add complexity to what would otherwise be a system where people figured out their best stat, then capped it. If crit is a warrior's best DPS stat, she'll stack crit until the cows blow up when she hits them, so by adding stats like hit and expertise you add a level where capping, reaching a certain level of X stat becomes a viable gearing strategy.
The problem is really that hit and expertise, because they do basically the same thing, don't serve us well. This especially becomes true when considering these stats alongside the other stats warriors will be using in their various specs. An arms warrior's relationship to hit and expertise is different from either fury or protection. This becomes even more complicated when considering SMF versus Titan's Grip, or hit/expertise/mastery tanks vs. mastery/dodge/parry tanks.