BS still uses the +50% bonus damage per disease for me on PTR, and HS is bugged in relation to BS :
Some data from the PTR using
[Large Club] without any weapon enchant nor proc trinket to have a perfectly stable AP (a premade was used).
PTR 0 disease
HS : 1258 hit - 3191 crit
BS : 1018 hit - 2591 crit
DS : 1294 hit - 3281 crit
PTR 1 disease
HS : 1852 hit - 4723 crit
BS : 1634 hit - 4140 crit
DS : 1293 hit - 3281 crit
PTR 2 diseases
HS : 2465 hit - 6253 crit
BS : 2246 hit - 5700 crit
DS : 1293 hit - 3282 crit
BS 1 disease / BS 0 disease = *1.6
BS 2 diseases / BS 0 disease = *2.2
HS 1 disease / HS 0 disease = *1.48
HS 2 disease / HS 0 disease = *1.96
So we can see that BS has a +60% damage bonus per disease, (+50%*1.2 from 4pt8), and HS as a +48% damage bonus per disease (+40%*1.2 from 4pt8).
Live HS bonus dmg per disease is +10%, and BS is +12.5%.
PTR HS bonus dmg per disease is +40% and BS is +50%
12.5/10 = 50/40, so it seems that BS and HS are still linked somewhere in blizzard's code :x
But if we correct the damage we can see that a BS crit with 4pt8 and 2 diseases up would do 2591*1+(0.25*1.2*2) = 4195 dmg where HS would do 3191*1+(0.1*1.2*2) = 3957
I was using a 1.6dps 2h, but i don't see why HS would scale better than BS with a 250dps and raid buffs.
Some calculation :
HS base damage = (50% weapon damage + 368) * (1+(disease count * 0.1))
PTR BS base damage = (40% weapon damage + 305.6) * (1+(disease count * 0.25))
HS damage with Bloody Strikes = (72.5% weap dmg + 533.6) * 1.2 = 87% weap dmg + 640.32
BS damage with Bloody Strikes = (58% weap dmg + 443.12) * 1.5 = 87% weap dmg + 664.68
HS damage with Bloody Strikes and 4pt8 = (72.5% weap dmg + 533.6) * 1.24 = 89.9% weap dmg + 661.664
BS damage with Bloody Strikes and 4pt8 = (58% weap dmg + 443.12) * 1.6 = 92.8% weap dmg + 708.992
Assuming 7000 average AP, 250 dps 3.4 speed weapon, 50% average crit on HS and BS abilities, Two-Handed Weapon Specialization, Blood Gorged, Bloody Vengeance stacked at 3, and a boss armor that reduce damage by 30% (we have a some armor pen) :
Without 4pt8 :
BS Hit Gain = 24.36*1.1*1.09*1.04*0.7 = 21,26316192
BS Crit Gain = BS Hit Gain * 2.45 * 1.03 = 53,65758910512
BS Avg Gain = 37,46037551256 per land
In a 6hs/bs rotation per 20s, it's a barely 11dps increase
With 4pt8 :
BS Hit Gain = ((7000/14*3.3 + 250*3.4) * 0.029 + 47.328)*1.1*1.09*1.04*0.7 = 104,594506016
BS Crit Gain = BS Hit Gain * 2.45 * 1.03 = 263,944235931376
BS Avg Gain = 184,269370973688 per land
In a 6hs/bs rotation per 20s, it's a 55dps increase which is better, but useless because in 3.2 t9 will be the main used set in 1 or 2 monthes.
If blizzard wants us to use BS over HS in a single target situation, either they have to up BS a little more, or to nerf HS.