Your logs were, well, interesting. In the 51/0/20 fight you cast IT 14 times, and PS 7 times. This is in comparison to the 50/0/21 log where you cast each 4 times. It wasnt exactly clear to me if you were using the same glyphs for both builds, if you were, that would be 1 problem to begin with. 51/0/20 would use Disease, DS, and DRW glyphs, and 50/0/21 would use Death, DS, and Disease. The other difference was the 50/0/21 had 10% higher uptime on Unholy Strength. Things to consider.

[e]: Hits/Crits seperate in logs, I'm dumb. Well one IT didn't hit so at least there's that difference.

I've tried to make a BiS set for Blood. I gathered the items in my sheet and created a rough set. My main question was: Is Arp worth stacking or not? So I tried to stack it without taking too many items with AP. So with 85% Arp I got this result (the other stats weren't interesting):

EP:50	Strength	284
EP:50	ArmorPenetrationRating	394

As a reference I created a set by taking the best items and stacking Str. I added an Arp proc trinket and got with 43% (100% procced):

EP:50	Strength	285
EP:50	ArmorPenetrationRating	320

Summary: Arp seems to scale very well.

I'm curious about your thoughts and especially results.
(In the simulator, go to the EP options and just check Str+Arp. That makes it a lot faster.)

Oh yes, one little point. My earlier testing where 50/0/21 was slightly better than 51/0/20 had following glyphs:

50/0/21 Death Strike, Dark Death, Unholy Blight
51/0/20 Death Strike, Dark Death, Dancing Rune Weapon

This would explain why my Deathcoils account for massive 13% of my damage and Unholy Blight for yet another 3%. If I'd lose Dark Death and replace it with Disease the rotation might actually shift enough to favor DRW over UB... Hmmm... I think I'll have to test THAT next time.

Not sure why WoL likes to tell me I cast IT so many times, since I'm 99% sure I never cast one more than the other.

I realize that, which is why I deferred to the bonus of DRW being a controlled burst when needed, which IMO is very useful for a lot of fights.

I've since been trying to get the DK Simulator to parse out the different spec and glyph options for my gear, but I don't know if it still calculates GoDisease completely accurately.

Well, you really didn't cast IT more. In the first log, you did hit with both 4 times. You also crit with both 3 times. In the second log, PS hit 7 times, crit 8 times, and was blocked once, totaling 16. Your IT hit 14 times, and crit 2 times, totaling 16.

So, here is what I found for blood DPS.

Droping GoDark Death and replacing it with GoDisease was a signifigant increase. I ran with different variations and Saw a 500-1k dps increase by throwing a pest at the end of the rotation and using 1 rune rather then throwing the dots back up. The increased dot damage makes it much higher priority then it was before. Then it becomes sort of a priority rotation. Pest > HS > DS ~ DC once around 80 RP. With this rotation, Sigil of Death Strike might be more beneficial as you're hitting it twice as much as before. Haven't done the math yet.

Also, the beneifit of going GoDisease is an extra Deathstrike and the ability to Heart Strike up to 6 times. I was thinking about doing this before the patch just because of the extra strikes = more dps then IT/PS.. but the dots were less damage.

Also, I've noticed a HUGE Difference with a 20 ARP increase...perhaps i've hit some sort of curve with my ArP but im wondering if gemming ArP would ever be beneficial? I would test it, but that's an expensive fix =x

How does GoDisease give an extra DS?

Without the glyph the rotation would be:
PS IT HS HS DS
DS HS HS HS HS

for 6xHS 2xDS PS and IT

With the glyph the rotation would be:

First time:
PS IT HS HS DS
DS HS HS HS P

Nth time:
HS HS HS HS DS
DS HS HS HS P

for 7xHS 2xDS 1xP

So what's really happening is PS and IT are being traded for P and HS. There are no additional DS to be gained.

That doesn't make any sense.

Let's look at a full rotation's available runes:

4xUnholy
4xFrost
4xBlood

Now with 2 DS, the number in the standard rotation, a full rotation's available runes becomes:

2xUnholy
2xFrost
4xBlood
4xDeath

This means that 2xDS is the maximum number of DS that can be cast in a rotation before death runes are used on death strike which is a DPS loss. GoDisease changes nothing about this fact and it should be obvious from the standard rotation that PS and IT are being used on death runes. When diseases don't have to be reapplied these runes are treated like any other death rune, as BS fodder.

So no, IT/PS/DS is not DS/DS every time with the glyph it's actually BS/P/DS. You gain rolling diseases and one BS and you loose IT, PS, and a major glyph.

You forget that the runes you use for IT and PS are 2 death runes, so instead of a DS you use 2x HS to replace them.

Technically you loose a HS somewhere in the rotation to cast Pest so it's better to think, in terms of net changes, that IT and PS are being replaced with HS and Pest.

I ran the simulator with the 51/0/20 blood spec (1/2 epidemic, 3/3 morbidity), blood priority, 2h Ulduar.xml file, etc etc just to generate some numbers to use to calculate the gains and losses of GoD and GoDD. Per rotation, based on runic power generation, you can do about 2.6 death coils.

GoDD: (glyph of dark death)
ITx1 = 1,965.0 dmg
PSx1 = 2,836.1 dmg
DCx2.6 = 13,982.8 dmg

total: 18,783.9 dmg

GoD: (glyph of disease)
Pestx1 = 0 dmg
HSx1 = 6,086.4 dmg
DCx2.6 = 11652.3 dmg (remember 15% less because you lose GoDD, GoD spec is 2/2 epidemic but 2/3 morbidity, so an additional 5% off 13,982.8/1.20 = 11652.3 [someone double-check if this is the right way to calculate that])

now adding the chance to proc a DC
11652.3/2.6 = 4481.7 dmg per DC
4481.7*0.15 = 672.3 dmg

total: 18411.0 dmg



However, I can't really take into account the effect of rolling disease, which would help GoD. I guess I could take the number of avg disease ticks per rotation from the simulator and total those up for GoDD, then guestimate or find the max disease ticks, which would represent the GoD when rolling with maximum trinket/FC procs. I also don't think the simulator accurately uses GoD, so that's why I couldn't just plug both specs into the simulator and run both to figure out which was higher on a whole cycle.

[edit, final remarks]
I do have experience in using GoD in a frost rotation, and it isn't as hard as one would think to keep diseases rolling from when you had the highest possible AP. I have a trinket's AP proc and FC up together often and early enough into the fight to keep them on the target for many cycles. So unless there's something else we are missing, once again it probably does come down to personal preference as Soilantgreen64 mentioned below.