There is no typo in the ArP/Expertise stat weights. ArP does scale that well - just as well as it did previously. Expertise simply goes up in value as the new SS goes up in value.

I'm still not having Reaping showing as a dps loss in current gear - yours Griefknight, mine (which is almost identical to yours), a generic 258 set, anything. And it stands to reason that it's no dps gain: the quick math a few posts back about Reaping's value was pretty realistic. SS is hitting for an average of almost exactly 10k at this gear level. IT + PS is hitting for almost exactly 7.5k at this gear level, which is 42 (~0.47%) dps a talent point. BA and DC are both still superior, by a not so negligible gap.

If you can post (or PM me, all the same) some side by side sims of the two spec, I can probably figure out what's up, but as it is, I still remain unconvinced as whatever I do, I simply can't replicate such results - nor can others I know and trust. Most importantly, though, just doesn't hold up to logic.

Anyways, in another area, yes, GoSS + No Epidemic + Morbidity is certainly possible. If you check the armory, that's actually what Potlol is running. The difference between that and GoDD + Morbidity is 5% DC damage, 3 extra seconds on your diseases on your primary target (RoR, if nothing else), and 6 extra seconds on your diseases on additional targets verse 10 second less cooldown on DnD. I just don't consider the latter near as valuable for a spec which is intended for primarily single target. On what fight are you going to use DnD that often without actually swapping to an AoE spec (assuming you aren't using a generalized spec to begin with)? Even on a fight like HM Anub, I don't get the chance to use DnD more than once per add wave, which would actually render Morbidity all but useless.

On a lot of single target fights, you're still going to be Pesting, and Epidemic helps there. On a lot of single target fights, you'll occasional DnD, sure, but not more than every 30 seconds.

Such is my take on it, anyways, but different playstyles will vary.

Edit: To be clear on DC and additional RP, you do want to use it. Yes, of course, obviously. You simply don't want to use it past the inherent empty GCDs of the rotation (which is plenty). For RP to start getting wasted as such you would need to be receiving an additional 300+ RP per minute from AMS/Revitalize/Etc, which is quite unlikely. It's really nothing to worry about.

I am also curious as to how much a change in dps there would be by using Morbidity instead of Necrosis. I started doing some testing on this but wasn't able to finish because a group moved in on my dummy and dropped it to 1 hp. Now I'm going to bed, hoping to pick up where I left off in the morning. I'd assume as you get more and more ArP and higher DPS weapons Necrosis would start to pull away by a decent margin.

I would like to question the first post on "10 second rotations being the thing of the past" With the buff to scourge strike from 3.2 to 3.3, and the nerf afterwards, I was wondering if the 3.2 17/0/54 spec with 2 points into morbidity instead of epidemic be a better option than the 17/0/54 spec currently shown on the front of the thread?

I do understand that the increased stats would cover the loss in APE from losing the 4-piece bonus of T9. But it probably wouldn't be a priority upgrade to be grabbed as soon as possible. The APE value difference between 4xT9 and 2xT10 is (457-234) = 223, which offsets a chunk of the stats you gain. So if there are better upgrades available I would take them instead.

Say I were to replace a level 245 belt with a level 264 one, I would similarly gain 19 i-levels worth of stats, without losing out in terms of the bonuses, just to quote an example.