Hit, expertise, and theorycraft
I'm fairly new to posting here, so I'm really sorry if this has already been discussed and answered anywhere.
I have seen a number of tables giving weights to various stats for various classes and specs. I really appreciate how concrete this makes gear decisions. There is however one practice in these tables that I have seen that I do not understand. That is the treatment of hit and expertise.
In tables, I usually see these stats given weights like any other, but this does not seem right. Whereas other stats are simply stacked for increased benifit, these stats are usually kept at hard cap, at least for dps classes. For this reason, I believe that the values assigned these are not entirely accurate. For instance, say a table values strength at 60 magical points, and expertise at 73. How is the expertise value obtained? In tanking, where expertise is rarely hardcapped and the value of reduced dodges/parries can be easily calculated, this makes sense. But for a dps? This is not a stat that should weigh like that. Imagine a set of expertise and hit stacked items past hardcap. Clearly this is not going to improve potential dps, even though it should by the table.
I would suggest that these values should be termed not from the value of expertise to dps, but from the value of other item points "freed up" to do other things. On this basis, what should it be? Should each point of hit be weighted the in terms of how much of the next best stat it could buy? For instance, should 40 hit be worth the same as 40 strength for fury warriors because removing 40 hit worth of gems would allow you to socket 40 strength? Or should there instead be a lesser value placed on these items, to reflect that in any real gear set, the hit or expertise added will free up item points that will probably be used for a less than optimal stats? Is there a way to average this effect?
Ultimately, I'd really just like to know what the general rule is for how these numbers are generated, and why. Thanks for your help!