Trespasser
OG
After some looking on the mmo-database I found some useful information.
I noticed that all the procs have much more detailed information there then on wowhead.
Looking at Fiery I found this table:
Fiery proc information
The interesting parts in this table are effect: school damage, base value: 39, dice base value: 1 and a die sides: 1.
What this means is that it does damage (effect: school damage). To be more precise it does 39 damage(base value). And it roles a 1 sides die(die sides) which has a base value of 1.
Since the die is only one sided the roll will always be 1. This is added to the 39base damage for a total of 40. Notice that this 40 is the damage the enchant is reporting when you look it up on say Enchant Weapon - Fiery Weapon.
Now lets look at the new Unholy Weapon on the mmo-database and we find 2 tables there.
Lets look at the second one first.
Unholy debuff information
Looking at the apply aura and the mod damage done we can conclude that this is the curse (apparently not actually a curse but a magic effect when looking at the Buff tooltip on the site) applied by the enchant.
And this time we find the base value: -16, dice base value: 1 and a die sides: 1.
again you will always roll one because it is one-sided (how the hell do you make a 1 sided die anyway) and this is added to the -16 and results in -15.
This is the of course the 15 reduced physical damage you will always see when looking up unholy weapon anywhere.
Now for the most interesting first table
Unholy damage proc information
The interesting parts in this table are effect: school damage, base value: 43, dice base value: 1 and a die sides: 13.
So we got a damage proc with a 43 base damage and the a dice is rolled with 13 sides starting with 1 and max of 13. The result is a damage proc with a minimum of 44 damage and a maximum of 56.
This gives a average of 50 damage.
Now to compare fiery with unholy weapon not taking into account the damage reduction part of unholy weapon.
Fiery weapon got a confirmed 6ppm proc rate. As for unholy I never found a reliable ppm for this one.
Because I don't have a proc rate for unholy lets calculate the proc rate needed to be on par with fiery.
Unholy vs Fiery calculations
Lets assume you are rogue with [item]Shadowfang[/item].
[item]Shadowfang[/item] got a 2.7sec swing timer this gives 22.222swings per minute. Since fiery got a 6ppm proc rate you should have 6 procs during those 22.222 swings.
6/22.222x100%=27% proc chance.
Now lets calculate the average damage per hit.
Every hit has a 27% chance to proc fiery so you get 0.27fiery proc per hit.
0.27x40damage=10.8damage per hit.
Now for unholy to have the same damage per hit we calculate it backwards.
10.8damage per hit / 50damage = 0.216 unholy proc per hit
0.216proc per hit means a 21.6% proc chance.
You are still using [item]Shadowfang[/item] so you still get 22.222swings per minute.
21.6%/100%*22.222=4.8ppm
Yes I know I could just have done 6/50*40=4.8 but I think A longer explanation might be wanted by some ppl.
So if unholy got a proc rate above 4.8ppm it will be doing more damage then fiery and if it is lower it will be doing less damage.
Now if it would have exactly a 4.8ppm proc rate it would ofcourse be better because it also apply's a debuff. But even without it it would still be better.
The reason behind this is because of the higher damage it is more bursty meaning it is harder to heal. Resulting is a higher chance for ppl to die before they can be healed.
Now if anyone could do some good unholy testing on the PTR with different weapon with different speeds on the lvl 1 target dummy. He/she might be able to give me a real ppm for unholy or maybe a fixed proc chance by hitting the target dummy over 1000 times without any abilities with each weapon while recording every thing with recount. Unfortunately I don't have a ally twink myself so I have no access to the lvl 1 target dummy.
Results with a fast weapon
Here are the results from my 1 hour test with unholy on a 1.3sec dagger on a lvl 80.

click for larger image
If we calculate the ppm with this data we get the following:
181procs / 2778 hits *100% = 6.515% chance.
This results in a 6.515%/100*(60/1.3)=3.01ppm.
This is the same as the small test run by Asterri.
Also notice that of all those 181procs there is not a single crit. While I had 5.79% spell crit during the test. So apperently unholy is unable to crit.
I am currently running another 1 hour test with a 3.4sec staff. So will be posting that information in 1hour from now. Together with dirrerence in dps between fiery and unholy with the proc rate I have found.
Results with a slow weapon
Here are the results from my 1hour test with unholy on a 3.4sec staff on a lvl 80.

click for larger image
If we calculate the ppm with this data we get the following:
181procs / (953hits+103crits) *100% = 17.14% chance (only used the melee hits and crits because the parry's and dodges can't proc it and my staff skill was to low so I got some parry's and dodges)
This results in a 17.14%/100*(60/3.4)=3.02ppm.
Calculations using the results of the tests
With the information I gathered with these tests I think we can conclude that the proc rate for Unholy Weapon is 3ppm.
Now what does this mean for the damage compared to fiery.
First we have to set the information for the calculations.
Lets assume you are a rogue with dual shadowfang and dual fiery and all you do is spam sinister strike with no points in imp SS with 5% hit rating and you are not going to be dodged or parried and you start with 0 energy.
If we want to calculate the total damage done by fiery over a time of 1 min (which we will devide by 60 for a dps) we first have to know how many SS's you can do.
As rogue gets 10energy every second for a total of 600energy during the 1 min.
This will let you do 600/45=13.33 sinister strike
Because you have 5% hit all your sinister strikes will hit.
Now lets see how many auto attacks you hit be making.
60sec/2.7sec swing speeds = 22.22 swings with both weapons because the swing speedis the same.
As a rogue you got a 24% base miss chance minus the 5% hit you got so 19% of your attacks will miss meaning 81% will hit.
22.22swings x 2 weapons x 0.81chance to hit = 36hits.
So during the 1 min you will have 36 melee hits and 13.33 sinister strike hits. For a total of 49.333 hits.
Now we already calculated with the 6ppm from fiery that the proc chance on a shadowfang is 27%.
So 49.333hits x 0.27proc chance = 13.32 fiey procs
13.32proc x 40fire damage = 532.8 damage over 60sec.
So we can calculate the dps for fiery in this case is 532.8/60= 8.88dps.
Now if we do the same with unholy we will still have the same amount of hits but a different proc chance and damage.
The proc chance for unholy on a shadowfang is:
3/22.222x100%=13.5%
So 49.333hits x 0.135proc chance = 6.66 unholy procs
6.66proc x 50shadow damage = 333 damage over 60sec.
So we can calculate the dps for unholy in this case is 333/60= 5.55dps.
So we can see that the use of dual unholy for this rogue is a 8.88-5.55=3.33dps loss or 3.33/8.88x100%= 37.5% dps decrease when only looking at fiery damage.
Now the question is if the increase burst and the lowering or enemy dps worth that 3.33dps
Also if we do the same calculation but with a rogue with a 100% uptime of SnD we get the following results.
fiery dps = 10.176dps
unholy dps = 6.36 dps
Or a decrease of 10.176-6.36= 3.816 dps or 3.816/10.176x100%=37.5% decrease when only looking at fiery damage.
Conclusion
So what can we concluse with the information I posted here.
First of we have concluded that the proc rate of Unholy is 3ppm
Second thing we can conclude is that the use of Unholy is a loss of dps compared to fiery.
And lastly we can say that the use of Unholy will probably become a enchant with a personel preference for some people. The same as fiery vs Lifesteal. Because some ppl might be willing to sacrafice a small amount of the to lower the damage done by you enemy and a increase in burst damage.
One last thing. Because I never seen any long testing on the fiery proc I might be trying to confirm the 6ppm proc rate on fiery later today.
I noticed that all the procs have much more detailed information there then on wowhead.
Looking at Fiery I found this table:
Fiery proc information
Code:
[b]Effect[/b] School Damage [b]Aura[/b] None
[b]Trigger[/b] [b]Proc rate[/b]
[b]Argument[/b] n/a [b]Value[/b] n/a
[b]Radius[/b] 0yd [b]Max. targets[/b] n/a
[b]Base value[/b] 39 [b]Dice base value[/b] 1
[b]Die sides[/b] 1 [b]Base / level[/b] n/a
[b]Interval[/b] 0 seconds
The interesting parts in this table are effect: school damage, base value: 39, dice base value: 1 and a die sides: 1.
What this means is that it does damage (effect: school damage). To be more precise it does 39 damage(base value). And it roles a 1 sides die(die sides) which has a base value of 1.
Since the die is only one sided the roll will always be 1. This is added to the 39base damage for a total of 40. Notice that this 40 is the damage the enchant is reporting when you look it up on say Enchant Weapon - Fiery Weapon.
Now lets look at the new Unholy Weapon on the mmo-database and we find 2 tables there.
Lets look at the second one first.
Unholy debuff information
Code:
[b]Effect[/b] Apply Aura [b]Aura[/b] Mod Damage Done
[b]Trigger[/b] [b]Proc rate[/b]
[b]Argument[/b] n/a [b]Value[/b] 1
[b]Radius[/b] 0yd [b]Max. targets[/b] n/a
[b]Base value[/b] -16 [b]Dice base value[/b] 1
[b]Die sides[/b] 1 [b]Base / level[/b] n/a
[b]Interval[/b] 0 seconds
Looking at the apply aura and the mod damage done we can conclude that this is the curse (apparently not actually a curse but a magic effect when looking at the Buff tooltip on the site) applied by the enchant.
And this time we find the base value: -16, dice base value: 1 and a die sides: 1.
again you will always roll one because it is one-sided (how the hell do you make a 1 sided die anyway) and this is added to the -16 and results in -15.
This is the of course the 15 reduced physical damage you will always see when looking up unholy weapon anywhere.
Now for the most interesting first table
Unholy damage proc information
Code:
[b]Effect[/b] School Damage [b]Aura[/b] None
[b]Trigger[/b] [b]Proc rate[/b]
[b]Argument[/b] n/a [b]Value[/b] n/a
[b]Radius[/b] 0yd [b]Max. targets[/b] n/a
[b]Base value[/b] 43 [b]Dice base value[/b] 1
[b]Die sides[/b] 13 [b]Base / level[/b] n/a
[b]Interval[/b] 0 seconds
The interesting parts in this table are effect: school damage, base value: 43, dice base value: 1 and a die sides: 13.
So we got a damage proc with a 43 base damage and the a dice is rolled with 13 sides starting with 1 and max of 13. The result is a damage proc with a minimum of 44 damage and a maximum of 56.
This gives a average of 50 damage.
Now to compare fiery with unholy weapon not taking into account the damage reduction part of unholy weapon.
Fiery weapon got a confirmed 6ppm proc rate. As for unholy I never found a reliable ppm for this one.
Because I don't have a proc rate for unholy lets calculate the proc rate needed to be on par with fiery.
Unholy vs Fiery calculations
Lets assume you are rogue with [item]Shadowfang[/item].
[item]Shadowfang[/item] got a 2.7sec swing timer this gives 22.222swings per minute. Since fiery got a 6ppm proc rate you should have 6 procs during those 22.222 swings.
6/22.222x100%=27% proc chance.
Now lets calculate the average damage per hit.
Every hit has a 27% chance to proc fiery so you get 0.27fiery proc per hit.
0.27x40damage=10.8damage per hit.
Now for unholy to have the same damage per hit we calculate it backwards.
10.8damage per hit / 50damage = 0.216 unholy proc per hit
0.216proc per hit means a 21.6% proc chance.
You are still using [item]Shadowfang[/item] so you still get 22.222swings per minute.
21.6%/100%*22.222=4.8ppm
Yes I know I could just have done 6/50*40=4.8 but I think A longer explanation might be wanted by some ppl.
So if unholy got a proc rate above 4.8ppm it will be doing more damage then fiery and if it is lower it will be doing less damage.
Now if it would have exactly a 4.8ppm proc rate it would ofcourse be better because it also apply's a debuff. But even without it it would still be better.
The reason behind this is because of the higher damage it is more bursty meaning it is harder to heal. Resulting is a higher chance for ppl to die before they can be healed.
Now if anyone could do some good unholy testing on the PTR with different weapon with different speeds on the lvl 1 target dummy. He/she might be able to give me a real ppm for unholy or maybe a fixed proc chance by hitting the target dummy over 1000 times without any abilities with each weapon while recording every thing with recount. Unfortunately I don't have a ally twink myself so I have no access to the lvl 1 target dummy.
Results with a fast weapon
Here are the results from my 1 hour test with unholy on a 1.3sec dagger on a lvl 80.

click for larger image
If we calculate the ppm with this data we get the following:
181procs / 2778 hits *100% = 6.515% chance.
This results in a 6.515%/100*(60/1.3)=3.01ppm.
This is the same as the small test run by Asterri.
Also notice that of all those 181procs there is not a single crit. While I had 5.79% spell crit during the test. So apperently unholy is unable to crit.
I am currently running another 1 hour test with a 3.4sec staff. So will be posting that information in 1hour from now. Together with dirrerence in dps between fiery and unholy with the proc rate I have found.
Results with a slow weapon
Here are the results from my 1hour test with unholy on a 3.4sec staff on a lvl 80.

click for larger image
If we calculate the ppm with this data we get the following:
181procs / (953hits+103crits) *100% = 17.14% chance (only used the melee hits and crits because the parry's and dodges can't proc it and my staff skill was to low so I got some parry's and dodges)
This results in a 17.14%/100*(60/3.4)=3.02ppm.
Calculations using the results of the tests
With the information I gathered with these tests I think we can conclude that the proc rate for Unholy Weapon is 3ppm.
Now what does this mean for the damage compared to fiery.
First we have to set the information for the calculations.
Lets assume you are a rogue with dual shadowfang and dual fiery and all you do is spam sinister strike with no points in imp SS with 5% hit rating and you are not going to be dodged or parried and you start with 0 energy.
If we want to calculate the total damage done by fiery over a time of 1 min (which we will devide by 60 for a dps) we first have to know how many SS's you can do.
As rogue gets 10energy every second for a total of 600energy during the 1 min.
This will let you do 600/45=13.33 sinister strike
Because you have 5% hit all your sinister strikes will hit.
Now lets see how many auto attacks you hit be making.
60sec/2.7sec swing speeds = 22.22 swings with both weapons because the swing speedis the same.
As a rogue you got a 24% base miss chance minus the 5% hit you got so 19% of your attacks will miss meaning 81% will hit.
22.22swings x 2 weapons x 0.81chance to hit = 36hits.
So during the 1 min you will have 36 melee hits and 13.33 sinister strike hits. For a total of 49.333 hits.
Now we already calculated with the 6ppm from fiery that the proc chance on a shadowfang is 27%.
So 49.333hits x 0.27proc chance = 13.32 fiey procs
13.32proc x 40fire damage = 532.8 damage over 60sec.
So we can calculate the dps for fiery in this case is 532.8/60= 8.88dps.
Now if we do the same with unholy we will still have the same amount of hits but a different proc chance and damage.
The proc chance for unholy on a shadowfang is:
3/22.222x100%=13.5%
So 49.333hits x 0.135proc chance = 6.66 unholy procs
6.66proc x 50shadow damage = 333 damage over 60sec.
So we can calculate the dps for unholy in this case is 333/60= 5.55dps.
So we can see that the use of dual unholy for this rogue is a 8.88-5.55=3.33dps loss or 3.33/8.88x100%= 37.5% dps decrease when only looking at fiery damage.
Now the question is if the increase burst and the lowering or enemy dps worth that 3.33dps
Also if we do the same calculation but with a rogue with a 100% uptime of SnD we get the following results.
fiery dps = 10.176dps
unholy dps = 6.36 dps
Or a decrease of 10.176-6.36= 3.816 dps or 3.816/10.176x100%=37.5% decrease when only looking at fiery damage.
Conclusion
So what can we concluse with the information I posted here.
First of we have concluded that the proc rate of Unholy is 3ppm
Second thing we can conclude is that the use of Unholy is a loss of dps compared to fiery.
And lastly we can say that the use of Unholy will probably become a enchant with a personel preference for some people. The same as fiery vs Lifesteal. Because some ppl might be willing to sacrafice a small amount of the to lower the damage done by you enemy and a increase in burst damage.
One last thing. Because I never seen any long testing on the fiery proc I might be trying to confirm the 6ppm proc rate on fiery later today.