Infraction: 6. Do not post unless you have something new and worthwhile to say.
Message to User:
I appreciate that you're trying to help, but I don't think you're answering the question that was asked. Eleven was talking about tanking in dps gear, you're talking about dpsing in tank gear. Both of these can be valid in the right situation. But comparing them, or saying one is superior, doesn't make sense. I suspect that's not what you were saying at all, but that you just didn't see the point Eleven was making.
Also, your statements about rune regeneration are wrong and confusing. With no haste and no presence, you regenerate one rune from each pair every 10 seconds. This means each pair has a 20 second cooldown, not 8 as you claim.
(Your point about crit is completely correct, I grant you that.)
First off my 2h stat priority is Str > Haste > Mastery > Crit.
First off, Crit has 0 tanking value in terms of EH as the DS heals nor Death pact can crit (I'm assuming it behaves like Lay On Hands since it is a percentage heal). While it is nice for tank DPS, it would be more beneficial to have a Dodge or Parry on the Boss's Swing table instead.
Now to why this works. Haste helps rune regen, and in blood presense you get 20% rune regen bonus. Thus allowing more deathstrikes. So with 30% haste (10/(1+(Haste%/100))) >>> 7.7 plus the 20% regen bonus >>> 6.2~ Rune Regen. That with whatever you use RC, RE, BT.....you end up with alot of extra Deathstrikes.
Your haste formula is incorrect. You treat the bonus from Blood Pres as a 20% haste modifier, so it gets added in before the other haste values:
10/[1+(20/1000] = 8.33 Rune regen.
Add Haste: 8.33/[1+(/100)] = 6.41 Rune regen.
Now most orthordox DK Tanks with no haste can DS once every 8 secs ~ before RC, RE, BT. So that normal tank takes 3 secs of dmg that doesn't help the next blood shield (because DS uses the last 5 secs of dmg taken).
You're a bit off with your Rune mechanics: Each pair itself has an 8 sec cooldown. So before factoring in your T75 procs, you have a cooldown of 4 seconds on Deathstrike; Plenty to cover the 5 second window before adding any haste. Additional Deathstrikes from Haste as well as from T75 procs will either overlap and not heal for the full 5 second window, or they will become minimal DS heals.
You would be better off (as a typical tank) to use your Mastery-heavy tank gear and go DW Frost, and still put our respectiful numbers (just trading out your 2H for 2 1H with appropriate enchants), especially if you gear for Hit and Expertise caps over avoidance.