Thank you for the quick response. So essentially should i just be gemming agi/agi+haste?

Since this is the combat guide, may I suggest not bloating it with references to the other spec(s)? Especially when the two sentences seem if not contradicting, at least confusing

Edit: Nevermind, misread Avalance for Hurricane which led to my confusion. Still, if Avalance is crap for Combat, why mention it. And the comparisons to assassination still seem a bit out of place.

It's one of two references (I think comparison is a better word) to Assassination in the guide, I think since most raiding rogues have played both specs at some point in time it's a fair reference in both instances. I decided it would be better to mention that Avalanche was not competitive instead of not mentioning it all because rogues are asking how Hurricane and Avalanche match up to Landslide as a cheaper alternative. This should give rogues a complete answer about current weapon enchants and not with the question "what about the other new enchant, Avalanche?"

While I understand that as a general rule, RvS should not be used if SS procs you from 3 to 5 combo points, does that also hold true when using it on an Eviscerate when you have 3 stacks of BG up? An extra 20% effectiveness on a finisher that's already 30% stronger seems to be worth using, especially when you have enough time on your SnD and Rupture that you're more or less spamming Eviscerates during that phase of Bandit's Guile.

Unfortunately I don't know how to go about calculating the value of the stronger Eviscerate vs. the value of the energy used to add a RvS when you don't need the CP.

It's also useful given that we may well be using the same weapon for both specs. Having an offhand dagger with an enchant which was gimped for Combat could very soon turn out to be expensive. Obviously seperate weapons with specialised enchants is the gold-plated answer, but knowing that Hurricane > Avalanche when used for both raiding specs is very definately worthwhile.

Another BG idea that may be unmodeled right now but I'd like to put it on the table. I was considering the circumstance in which AR comes off cooldown while in a state of Deep Insight. There are two possible options, pop it right away to get extra abilities and haste within Deep Insight, or save it for when Deep Insight falls, so that you can use your extra SS / RvS to get you back into Deep Insight.

Also it's been modeled that Killing Spree is best saved for Deep Insight, but on certain fights it becomes quite difficult to use Killing Spree at this point. The best example of this is Nefarian. By the time Deep Insight has piled up, there are adds in the way that could potentially drag my KsP away from the boss. Is it advised to cross fingers and hope it doesn't hit adds, wait until adds are gone, or just pop KsP right at the start before adds even come into play? (I'm leaning towards the latter, seeing as the earlier it is done the more the cooldown has been chopped by RB)

If you find you can reliably wait for BG to stack up and not get pulled off onto adds, you should. If you can't, you shouldn't. There's no general answer - it depends on your guild's placement, your ability to judge safe distances and timing, etc.

It might feel like you're getting close to the cap, but you're really really not. At 1686 haste at current early raid gear levels, your baseline energy regen is probably around 17 a second, which means you're probably only looking at a move every 2 seconds on average. And given that the GCD is 1 second, this would imply a fair amount of cushion in the rotation yet.

I mean, lets be clear: Combat is very spammy, and it caps energy very quickly when you stop attacking. But that's fundamentally just the nature of the cycle - even with zero haste, you'd be up around 15-16 energy per second, and the fact that every single stat you have (save crit) boosts your regen directly or indirectly means that's only going to go up. Combat is just going to play that way, and there's just not that much we can do about it. If you don't care for that playstyle, that's totally understandable - as it happens I agree, which is among the reasons I'm running Assassination instead. But its not something you can really fix through itemization, either - the problem is in the fundamental design of the spec and the way it overloads energy regeneration as a damage-increasing mechanism, not with the way we're itemizing it. Its much spammier than any spec we've had to play before, and that's just something you have to get used to if you want to play combat.

It seems everyone is focusing on the primary benefit of the meta and not on the requirements. I have long assumed that, until CSD and RED are fixed, [Destructive Shadowspirit Diamond] would be the best option. If you already have a yellow and a blue in your gear naturally (which is by no means guaranteed or even remarkably common) then thundering may give it some competition - though there has been little testing and the numbers are dubious. Runspeed is really the only thing getting in the way (which makes this more relevant to assass) but I find that there are virtually no situations where a sub-1 minute cooldown sprint isn't more than suffucient for full time on target. And if you disagree and still want runspeed, get it on your boots at the cost of 10 agi and then collect an extra 40 by gemming full agi with this metagem anyways.

That's been my approach, thought I'd throw that out there.

Speaking as an Combat and Assassinatio rogue rogue, the nubers of the 3 meta gems in discussion is what matters in terms of dps.

Combat:
The [Destructive Shadowspirit Diamond] gives: 54*0.95 = 51.3EP and some minor survivability gain.
The [Fleet Shadowspirit Diamond] gives: 54*0.9 = 48.6EP and minor run speed increase.
The [Thundering Skyflare Diamond], assuming an optimal up time (6sec /45 sec ICD) at ≈13% => (480*1.5)*0.13 = 93.6 EP.

The [Fleet Shadowspirit Diamond] might be slightly better based on the latest bluepost regarding a possible buff to Combat mastery.

The obvious choice will be, as they fix the requirement, and also staded in the guide, will be [Relentless Earthsiege Diamond].

Assassinaton

The [Destructive Shadowspirit Diamond] gives: 54*0.9 = 48.6EP and some minor survivability gain.
The [Fleet Shadowspirit Diamond] gives: 54*1.3 = 70.2EP and minor run speed increase. (You will not gain any additional runspeed when specced into Quickening as the talent does not stack).
The [Thundering Skyflare Diamond], assuming an optimal up time (6sec /45 sec ICD) at ≈13% => (480*1.2)*0.13 = 74.88 EP.

Also here the [Fleet Shadowspirit Diamond] will be the upper crust choice when they fix the requrements.

[Edit]

For the requirements, the Thundering is no problem meeting, I use pure agi in red, orange with agi mastery (assasination) / agi Haste (combat), and agi hit for the blue ones. As far as socets go, you should not have any problem obtaining gear with one of each socket to not vaste a socket bonus.

[Edit2]
Added the part about runspeed on the [Fleet Shadowspirit Diamond] for Assassination.

My combatlog includes:
minimum time between 2 applies/casts: 40.118 between casts(4&5) (line 986 1128)