I am not entirely sure this is where I should be posting this (my first ever post here), but I did some calculations regarding combat potency and hit% vs crit% to see how they compared. I couldn't find any posts covering this topic, apologies if there is one already.
There are two major factors not covered here: application rate of poisons, and “chance on hit” procs.
I am assuming that we have 5/5 Combat Potency, 5/5 Precision, hit rating higher than the one-hand miss rate but lower than the dual wield miss rate. Firstly I’ll focus solely on white damage, showing that increasing hit by 1% is exactly the same as increasing crit by 1%.
We know that hit% + crit% + miss% = 100%, and increasing hit rate decreases miss rate, while increasing crit rate has no effect on miss rate. Look it up. It’s true. So a HIT is in fact only a move that neither missed nor crit.
Ok so let’s say that your hit% from gear is H, crit% from gear is C, your base chance to miss is 19%, and your average weapon damage is D.
DMG = (chance to hit AND NOT CRIT) * (average weapon damage) + (chance to crit) * (average weapon damage) * 2
= (1 – 0.19 + H – C) * D + 2 * C * D
= (0.81 + H – C + 2 * C) * D
= (0.81 + H + C) * D
From that it should be fairly obvious that increasing either H or C by the same amount has the exact same result. Therefore we can ignore white damage completely when determining the affect of hit vs crit on overall dps.
Now that that’s out of the way we can get on with yellow damage.
The affect of hit percent
The last thing I want is to turn this into an argument about Sinister Strike and Backstab, so I’m not even going to mention either when working out the affect of Combat Potency on yellows. Instead I’m going to say that your entire spell rotation has an average total damage caused, divided by the total energy cost (including Slice and Dice) to give you your yellow
damage per energy or DPE. Over any given period of time, the yellow damage you deal is your DPE * (amount of energy generated). Increasing hit percent wont change your DPE since we are already past the hit cap for yellows, and as such the only factor we need to consider is how much more energy we generate over any given time.
Normal energy generation:
Energy = 20 energy per 2s * time = 10 * T.
Energy generated from Combat Potency:
Energy = (number of offhand swings) * (offhand hit% including crits) * 20% * 15 energy
= (T/S) * (0.81 + H) * 0.2 * 15
= 3 * T * (0.81 + H) / S
Total energy generated:
Energy = normal energy generated + potency energy generated
= 10 * T + 3 * T * (0.81 + H) / S
= T * (10 + 3 * (0.81 + H) / S)
OR
Energy per Second = 10 + 3 * (0.81 + H) / S
Where T = time; S = offhand weapon speed; H = hit percent from gear.
Let’s assume that we have a 1.3s dagger in the offhand, and Slice and Dice is always up, so we can say S = 0.91s. Solving this for every value of H gives..
Hit% NRG/s Increase %
===================================
1 12.7032967 -
2 12.73626374 100.2595156
3 12.76923077 100.2588438
4 12.8021978 100.2581756
5 12.83516484 100.2575107
6 12.86813187 100.2568493
7 12.9010989 100.2561913
8 12.93406593 100.2555366
9 12.96703297 100.2548853
10 13 100.2542373
11 13.03296703 100.2535926
12 13.06593407 100.2529511
13 13.0989011 100.2523129
14 13.13186813 100.2516779
15 13.16483516 100.251046
16 13.1978022 100.2504174
17 13.23076923 100.2497918
18 13.26373626 100.2491694
19 13.2967033 100.2485501
This is at most an increase in yellow damage of 0.28% for 1% increase in hit percent.
The affect of crit percent
Increasing crit by 1% does nothing more to yellows than increase the amount of crits by 1%. This is complicated by the fact that not every spell can crit (such as Rupture), and due to Lethality, not all crits increase damage by the same amount (e.g. Evicerate crit is 2 * D, Backstab crit is 2.3 * D).
Ok so as before we should talk in terms of damage per energy for yellows, and since our hit percent isn’t being changed here the amount of energy we generate won’t be changing either. Therefore what we need to calculate is how much more damage we do for each percent of crit added.
There are three different types of yellow we need to consider: Moves that are affected by Lethality; moves that are not affected by Lethality; and moves that can not crit at all.
Lethality
Crits do 230% normal damage. The hit cap for yellows has been passed already so we can assume there will be no misses.
DMG = (1 – C) * D + 2.3 * C * D
= D * (1 – C + 2.2 * C)
= D * (1 + 1.2 * C)
where D = average non crit; C = crit chance
Changing our crit chance will have no affect on the average non crit, so we can say that our damage per energy will increase only as (1 + 1.2 * C) increases.
Choosing a range of crit chances to test this over of 20% to 50% (I’m assuming no one will have lower than 20% or higher than 50% crit) we get:
Crit% 1+1.3C Increase %
===================================
20 1.26 101.04250200481154
21 1.273 101.03174603174604
22 1.286 101.02120974076982
23 1.299 101.01088646967341
24 1.312 101.00076982294074
25 1.325 100.99085365853658
26 1.338 100.9811320754717
27 1.351 100.97159940209266
28 1.364 100.96225018504812
29 1.377 100.95307917888562
30 1.39 100.9440813362382
31 1.403 100.93525179856115
32 1.416 100.92658588738418
33 1.429 100.9180790960452
34 1.442 100.90972708187545
35 1.455 100.9015256588072
36 1.468 100.893470790378
37 1.481 100.88555858310626
38 1.494 100.87778528021609
39 1.507 100.87014725568943
40 1.52 100.8626410086264
41 1.533 100.85526315789473
42 1.546 100.84801043705153
43 1.559 100.84087968952134
44 1.572 100.83386786401539
45 1.585 100.82697201017811
46 1.598 100.82018927444796
47 1.611 100.81351689612013
48 1.624 100.80695220360025
49 1.637 100.80049261083742
50 1.65 100.79413561392792
Non Lethality
This will be the same as Lethality with the exception that crit damage is 200%.
DMG = (1 – C) * D + 2 * C * D
= D * (1 + C)
Which gives...
Crit% 1+C Increase %
===================================
20 1.2 100.84033613445379
21 1.21 100.83333333333334
22 1.22 100.82644628099173
23 1.23 100.81967213114754
24 1.24 100.8130081300813
25 1.25 100.80645161290323
26 1.26 100.8
27 1.27 100.7936507936508
28 1.28 100.78740157480314
29 1.29 100.78125
30 1.3 100.7751937984496
31 1.31 100.76923076923076
32 1.32 100.76335877862596
33 1.33 100.75757575757575
34 1.34 100.75187969924812
35 1.35 100.74626865671641
36 1.36 100.74074074074073
37 1.37 100.73529411764707
38 1.38 100.72992700729927
39 1.39 100.72463768115942
40 1.4 100.71942446043164
41 1.41 100.71428571428572
42 1.42 100.70921985815603
43 1.43 100.70422535211269
44 1.44 100.69930069930071
45 1.45 100.69444444444444
46 1.46 100.6896551724138
47 1.47 100.68493150684932
48 1.48 100.68027210884354
49 1.49 100.67567567567568
50 1.5 100.67114093959732
Uncrittables
These won’t change at all no matter how much crit you have, and so the increase percentage is always 100%.
Combining the Crits
The best I can come up with to combine the crit increases so far is to have the person find out what percentage of their total yellow damage each type does at their current crit rate.
A + B + C = 1
where A = Percent of damage dealt by Lethality moves; B = Percent dealt by non Lethality moves; C = Percent dealt by uncrittable moves
Then increase the crittables by the Increase% of the next crit% in the tables we worked out earlier.
INC% = X * A + Y * B + C
where X = Increase% from Lethality; Y = Increase% from non Lethality
Let’s say for example that our crit is 30%, and that our spell rotation breaks down to A = 0.5; B = 0.2; C = 0.3. We would have:
INC% = X * A + Y * B + C
= 1.00935 * 0.5 + 1.00769 * 0.2 + 0.3
= 0.504675 + 0.201538 + 0.3
= 1.006213
= 100.6213%
Rather than work out a lot of different tables of data for every combination of A, B and C, I’ll just look at the worst case that could reasonably occur: No moves are affected by lethality, and more than half our yellow damage comes uncrittable moves. Since this is a worst case I’ll assume the person’s crit rate is already quite high, say 45%. The point we need to find here is where the increase% falls below 100.28 (i.e. the best case for hit)
A = 0; B = 1 – C; 0.5 < C < 1; Y = 1.00689.
INC% = X * A + Y * B + C (A = 0)
= Y * B + C (B = 1 – C)
= Y * (1 – C) + C
C Y*(1-C)+C
=================
51 100.33761
52 100.33072
53 100.32383
54 100.31694
55 100.31005
56 100.30316
57 100.29627
58 100.28938
59 100.28249
60 100.2756
61 100.26871
62 100.26182
63 100.25493
64 100.24804
65 100.24115
66 100.23426
67 100.22737
68 100.22048
69 100.21359
70 100.2067
So given the worst possible spell rotation for crit, uncrittbale moves would have to account for at least 60% of your yellow damage in order for hit to give you more of an increase than crit.
This goes against 90% of what is said about rogue dps, so what I’m mainly after from posting this is to have people find any flaws in my assumptions or in my calculations.
EDIT: Yeah dunno why but I worked all this out with Lethality being an extra 20% dmg rather than 30%, fixed now.