I'm just pasting for the EJ thread.
Source:
http://elitistjerks.com/f78/t38187-free_hat_deep_subtlety_you/p5/Spec:
http://www.wowhead.com/?talent=fhbbZ0gc0x0xoZxbcbhGkdAzqcAnd the notes:
Since Apps specced HaT before our raid the other night, I've been interested in this build. I have very little knowledge of the rogue class, so while I can't answer any questions, I can bring up a few points which I believe can increase the dps of this spec by roughly 5-10%.
1. If you believe rupture is worth keeping up (this has been debated here), a good spec would be 7/21/43 and glyphs be Evis/Rupture/SnD. Note: Rupture increases its value if you have 2pT7.
2. If you don't believe rupture is worth keeping up, a good spec would be 5/21/44 with 1 talent point to put in either Malice or Precision. Your glyphs would be Evis/SnD/Hemo or Prep. Both Hemo and Prep glyphs won't be worth a lot, but seem to be the only glyphs that would increase dps at all.
Thoughts about cooldown management:
Much like mages in TBC, the difference between a good HaT rogue and a bad HaT rogue will be getting the most out of your cooldowns. Obviously keeping SnD and/or Rupture up will be key as well, but proper cooldown management will be a fairly nice boost to your dps. Since rogues with this spec don't have many cooldowns, this basically centers around using Vanish and taking advantage of the talent "Master of Subtlety".
To maximize your cooldown usage (and assuming that a fight lasts for about 4 minutes, with bloodlust coming at 35%), you would want to do the following:
1. Start with a Premeditation followed by Garrote or Ambush and use Blade Flurry (Master of Subtlety kicks in and gives you 10% more damage for the first 6 seconds)
2. 20 seconds after that, Vanish, Premed, Garrote or Ambush again (gaining 10% more damage for 6 seconds)
3. At 35%, all of your cooldowns should be back up again and gain Bloodlust. Vanish -> premed -> garrote or ambush -> Blade Flurry (10% more damage for 6 seconds)
4. Use Prep. At this point, I'm not sure if you should Vanish again after the 6 seconds (to gain more from your blade flurry), or use vanish after premeditation is off cooldown. Either way, vanish -> premed if able -> garrote or ambush (obviously don't garrote if you use after 6 seconds as the debuff will still be up) (10% more damage for 6 seconds)
As for gear choices, the first priority should be to cap your hit with yellow attacks (8% or 5% with 3/5 Precision) and cap expertise (26 Expertise). I stress this point because it seems that having a combo move missed or dodged will really hurt your dps as relentless strikes will not give you 25 energy at that time (Am I correct on this or does it give you the energy regardless of hitting/missing/dodging?)
The other thing I'm unsure about is if poisons have 2 chances to miss. First, the weapon has to hit (affected by your melee hit %) and then the poison can resist (affected by your spell hit%). If this is the case, you would want to stack much more than the 5% hit required to cap the yellow attacks.
Anyway, just a couple of things to think about to try to max your dps. Let me know if I'm incorrect on anything and I'll change it. This is all coming from a feral druid point of view so it may be inaccurate.