I'm sorry but I didn't understand your math at all. 30,875 spell power? I don't even think you have that much spell power to lose. Either way, I woke up this morning realizing that I did the calculation for MC increase in damage wrong. So I re-did it, and it came out that (3/3) Cataclysm is better than (2/3) MC. But point by point, MC is higher DPS than Cataclysm.
So, the point I'm trying to make is that hit capping your destruction spells with Cata, when your affliction spell are hit capped by Suppression, by taking points in Cataclysm over MC is less DPS overall for you. That means that there's no change in your gearing, since gemming for hit has been shown to be less DPS. And going over hit cap in affliction is also a waste in talent points. (aka. if you hitcap yourself with gems in affliction, then those 3 points in Suppression should be going to some other DPS increasing talents which would make these calculations more complicated than necessary.)
So we're doing a pure talent to talent comparison.
Let's take my WWS report from Patchwerks where I was hitcapped with Affliction but had a 97% hitrate with Destruction:
Wow Web Stats
DPS Lost
I had a 2.1% miss rate with Shadowbolt (or 1 missed hit) and 6.7% miss rate with Immolate (or 1 missed hit). On average my Shadowbolt will hit for:
Average hit * (1-crit rate) + Average crit * crit rate = 4541*.62 + 9186*.36 = 6122.38
Assuming that when I miss Immolate, I'm missing 1.5s of filler. Therefore, total damage lost is:
6122.38 [lost SB] + 6122.38*(1.5/2.5) [lost filler time] =
9795.808 damage or 9795.808 damage/3min 57s =
41.33 dps or
13.77dps per point
DPS Gained
Next, let's look at the DPS gained via MC. By going into the log and filtering it to see my MC refreshes (since they don't count as buff gained in the buff tab), I can calculate my MC uptime:
Wow Web Stats)
It shows me that MC was down between:
02:08'16.750->02:08'35.218 = 18.468s
02:09'36.437->02:09'42.297 = 4.86s
02:09'58.453->02:10'08.640 = 10.187s
02:10'18.640->02:10'38.234 = 19.594
02:10'52.281->02:10'59.484 = 7.203s
Death occured less than 10s after the last refresh.
Total MC-down time= 60.312s
Total MC-up time = 237s-60.312s = 176.688 OR 176.688/237 = 74.55% up time
So we're going to simplify this and make the assumption that this up time will give us 75% of all direct damage with MC and 75% of all DoT ticks with MC (so MC is distrubuted evenly with all DoT ticks and Direct Damage hits and criticals.)
So, let x = the total damage of Immolate without MC.
x*1.1*.7455 + x*(1-.7455) = 112855
.82005*x + .2545*x = 112855
1.07455*x = 112855
x = 105025.35
Therefore, total damage increase by MC is:
.1*.7455*105025.35 = 7829 OR 7829/237 =
33.03 dps or
16.515dps per point
Now, the problem with this is the fact that the 3rd point of MC would at most cap out MC uptime (so it would do less than the previous two points.)
So lets assume that we have 100% MC uptime with 3/3, then the MC damage increase would be:
105025.35 (x) * .1 = 10502.535 or
44dps or
14.77dps per point on average.
Therefore, 1 point in MC is 1dps more than 1 point in Cataclysm. (A trivial difference really.)
Now I have a question. I take 2/3 MC because that's all my spec allows for, since I take 2/3 Eradication. Is the 2nd Eradication point more DPS than the 3rd point of MC?