Originally Posted by Astalion

A spec I haven't seen posted that seems to be competitive is this: 10/54/7.
Best options seem to be using BP, FC/RI (RI seems to be far superior to FC, especially with the increase to 10%), and SoA (quick simulation showed a large (~175 dps) difference in favor of SoA, no comparison made with the new Sigil yet)

I've been running my simulations on a modified version of Kahorie's simulator (added information I could find in this thread such as sigils not being affected by the offhand penalty, runes only being consumed on main hand hits, razorice stacking up to 10%, and just now (aka after most of my testing) the 15% increase to disease damage and SotVH nerf). I also added the hit from Heroic Presence, which might affect gear choices but hopefully (likely) not much else. (Simulations with the BiS gear below ended up at around 6.9k dps, but keep in mind that most of the changes I made to the simulator lead to increased DPS (but more accurate) values compared to others' simulations, and as such you probably should run your own simulations on this if you want some numbers for comparison)

Original tests were done using my own DKs T7/T7.5 gear, but from further testing it seems to scale properly with T8 BiS gear as well.
BiS Gear stats used for those interested: Str: 1426, Agi: 245, Int: 46, Arm: 14291, Hit: 177, Crit: 752, Haste: 255, Arp: 160, Exp: 179, OH/MH: 178.9dps/2.7s, 4p T8
Yes, the hit is kinda low, but from EP calcs it actually doesn't seem to be that important (melee hit cap being a lot lower due to NoCS, and relatively few spells used)
LootRank listing (EP values derived from the T7 gear, being below spellhit cap. Above the spellhit cap the value of Hit falls to roughly 0.77 (or 77 with AP set as 100, but lootrank isn't a fan of big numbers :P). Note: Kahorie's calculations seemed a bit dodgy regarding weapon dps and weapon speed EPs, so I made some calculations of my own which halved the listed value of MH weapon dps, but makes more sense matematically, unless I missed something :P)

Priority used was: FF > BP > OB > BS > FS > Rime
With the T8 4P bonus moving BS above OB seemed to give a few (<10) DPS increase from a few short tests (2*24h simulations on each), and with proper estimation of free GCDs (taking into account Rime procs and such) it might be a worthwhile tactic for maximising DPS, but doesn't really seem worth the hassle in my opinion.

I also did some tests using Glyph of Disease instead of Glyph of Blood Strike, and it seems to be a DPS loss of about ~40, but still being better than using any other Glyph. (Note: The simulator's priority system doesn't take full advantage of this Glyph, and has to reapply disease with PS/IT fairly often even with it. In practice Glyph of Disease might actually be superior)

As for the Blood Strike Glyph, if you need to get Chillblains (did we get confirmation on whether this actually worked on bosses?) the best point to move seems to be UA (Though I once again wonder if this is something the simulator uses properly, and you might want to have both a dps and a survival cooldown for various bosses, in which case you probably want to move a point from Black Ice instead (didn't test that extensively though))

Hopefully this will help narrow down some of the questions in the OP and possibly help decide the spec to use in 3.2.