Arms started the tier out fine with the new buffs we got for 5.2, but now that the weeks have gone by, it's becoming increasingly clear that the trend right now is that arms is going to be end up as one of the bottom specs again before 5.3. I've been keeping up with raidbots as much as I can and it doesn't look good.
Problems with arms? The same problems as last tier that were ignored. Whereas arms last tier was kind of fun to play, arms this tier is mindless with the notion that we got "buffed".
1) Very horrible burst and bad cooldowns. This was an issue last tier already, when we got barely any benefit from heroism and were reliant on procs to do good burst at the start compared to other classes. However, we had 50% recklessness so it wasn't as bad as it is now - where 30% recklessness is just too RNGish. Overpower was ONLY part of our rotation last patch instead of being a core skill, so recklessness benefited us more back then, whereas now it's mostly wasted on slam to hope for crits.
2) Bad Cleave and AoE. Before you bring up Tclap/deep wounds, hear me out. The fights right now are leaning towards burst aoe, not sustained. What this means is that deepwounds never reaches it's potential most of the time. Add to the fact that sweeping strikes is a very hefty costing cleave and that arms is just not very good at generating rage to spam whirlwind well enough, and you get this.
3) Scaling. Always our biggest problem. Always the one that GC seems to dismiss as nonsense. While mastery and haste got buffed to be decent this time, I don't feel it's to the point where we can keep up with other classes as everyone gears up. Case and point - Primordius. There's a reason arms is THE very bottom DPS spec for this fight.
There is NO reason to play arms in a raid at all with all those problems, besides the fact that you have fun with it - which I don't see how it's possible considering how the spec got gutted into it's playstyle now. I really loved the old arms and I wish they stuck with it and made it do more damage, but when they buffed the damage at the cost of simplifying the playstyle to be mindless, I was fine with it as long as arms could keep up. It can't.
Are we just going to get buffed again next tier so we do well again at the start and yet fall behind again later on? I really hope not.