Just also throwing out another angle to the arcane discussion beyond just the numbers.
The burn/burst cycle with all CDs used seems to have been hardly affected by the changes. As noted previously, changes to AP coupled with the AM glyph, amounts to a very minor DPS loss. The burn/burst (ABSpam3Mbarr) isn’t affected by the ABarr nerf either.
So, among all the DPS specs, it seems to me like Arcane still retains the best ability to deal ‘burst-on-demand’, when needed. Now of course this is situational, but it is also a point of differentiation – and I might argue that it is perhaps a very distinct point of differentiation as well.
The reality is that there are a lot of other things that are situational within a raid; composition, other player skills, differing gear levels, different raiding strategies etc. In some situations, you may not even want to use arcane even if it was doing better DPS (having raided the past 2 weeks with our only survival hunter and spriest away has made mana a strained resource as far as arcane goes – we also only had 1 paladin judging wisdom), in other situations you may have the luxury of choice or you may be required to spec for the raid as opposed to yourself.
I’m definitely not discounting the amazing work the TC’s here have done. It’s good that we all know where each spec stands in terms of bottomline numbers. But I think that at some point the ‘intangibles’ also come into play.
I guess one other question we can sometimes ask is, assuming all 3 mage specs are equal in terms of DPS, and all other factors (Rotation dynamics, RNG, MPS, Mobility etc) are still at play depending on spec, then what spec would you as a player be most comfortable playing?
Sorry if this is a little off-topic but just putting it out there
