This is a long long long post, im sorry but it needs to be this long to actually answer all the questions.  You need to be able to understand the games mechanics acurately before just accepting their description. 

First off the math behind melee damage is slightly confusing.  Most of the class leads I talk to assume its 66% main hand and 33% off hand.  Which is true, the total melee dmg is 66% from the main hand and 33% from the off hand.  Okay, gold star 1.

Here is where the general confusion is.  Calculating the individual damage per hand seems to be the thorn in most people’s mathematical sides.  So for simplicity lets use 2 identical weapons so we don’t have to consider the difference in delay (although I will touch this later).

For simplicity, let us assume you have 2 tier 5 heroic crafted fist wraps.  Each has 139-152 damage, so let us just say each one is 150 damage.  So you have 150 damage main hand weapon, and 150 damage off hand weapon.  Now let’s look at the damage bonus from strength.  If you have 300 strength, you gain about 250 additional damage (according to the tooltip. 

So where does that 250 go? Is it main hand or off hand, is it 66% to the main and 33% to the off hand?  Nope.
To calculate melee damage from weapon damage and strength, you add them as 100% vs 50%.  So you main hand is 150 dmg, and you have 250 bonus damage from strength for a total of 400 melee damage main hand.  This is with no modifiers and really low strength at 50.  So what is the offhand? Its 50% weapon damage + 50% strength bonus, aka 75+125.

How do you figure melee damage at 50 with %damage modifiers?
Well its really quite simple.  It is easiest to see with 2 identical weapons, but to start you use the equation above (weapon damage + strength bonus) and you multiply by the % damage modifier you have.  A fully buffed raid monk will have +50% damage (+30% if they are harmonious).  So that becomes (150+250)*1.5 for your main hand and (75+125)*1.5 for your off hand.

So where does flat damage apply currently and how is it affecting melee damage
Okay so we have 2 equations now, one for main hand and one for off hand, and we are almost caught up to the point of asking about combat arts, just 1 last side step… flat damage.  So flat damage comes in 2 flavors.  The first is the more common +200 damage to melee attacks (aka iron hands) and the other is +200 damage to the next hit (jin surge).  Jin surge is simple, it adds the +200 damage after everything else and just increases the combat art by 200 damage total.

Iron hand is more complex, because its adding to melee damage, its adding +200 to the main hand… and you guessed it +100 to the off hand, but its adding them after everything else (similar to how fusoya explained.
So for main hand: (weapon damage+strength bonus)*damage modifier +flat damage.  In our example it is (150+250)*1.5+200 (iron hand). 
The off hand is again, (75+125)*1.5+100. 

Where do true flat damages apply?
Jin surge is the only true flat damage I have as a monk.  For a single target hit like this, it adds the +200 damage to the final damage, so that 2250 damage thunder fist, now hit for 2450 damage.  Specifically, 66% of the 200 was added to the main hand and 33% to the off hand.  Cool so, that makes sense from everything we’ve been told.

How does Fist of celerity/quick blade/ errant strike actually work at the moment?
While Fusoya’s post isn’t incorrect, it is very misleading as to how the skills currently work and why they work the way they do.  In general these skill double the damage of a combat art by repeating the hit.
Ashen hand is a good example to start with.  Lets just assume a regular ashen hand hits for 5000 damage, poping any of the double damage buffs, has the net result of taking the damage from 5000 to roughly 10,000.  So take a minute and look at the combat log now.  You will see something like “you quickly strike for 5,420 damage. Your ashen hand hits for 10,340 damage”.  The net result is that you doubled the damage of the combat art.  So how is it actually doing it?  Its not taking your hit and multiplying it by 2.  Its just letting it hit twice, which is why you get natural variation.  If the log had even more details you would see…
Quickly strike for 5430 damage…Ashen hand for 5203 damage… Total hit 10k.
So, it really is just letting you hit it twice, which means the doubled hit could be less or more then the original depending on the range of damage you naturally get on that hit.


How about monks with fist of celerity and errant strike up
For the life of me I cannot replicate Fusoyas bug of hitting for over 100k.  I can with critical hits and both double damage hits, get up to about 75-100k.  So that aside, I will explain this as I see it in my combat logs after doing it 10x while on a raid.
So at first glance you would assume using 2 double damage buffs would have a huge effect making a 5k hit do 20k.  Instead it only does 15k?  Why is that?  It is because its just letting you hit two additional times.  So if you are actually doing 5k+5k+5k…. not 5k*2*2.  It’s a big difference, but I believe this is how it should be as the other way would be way more inflated with damage. 


Double damage and Critical hits
So the first major issue in my eyes, is that if your original hit criticals, you get 2 follow up critical.  Ideally what should be happening is that, each of the “additional” hits should have its own unique chance to crit. 

You understanding of the +damage bug is skewed.  Your example is how it is going to work after the fix.  Go re-read Talisker's post to see how it is working now.  When you combine massize +flat damage buffs you get in a raid, with that damage being applied multiple times to the same attack is where you get the problem.  In solo/group play you will barely notice any difference pre/post dps fix.

Actually i have it right, they just have their definition of flat damage wrong.

The thing is most of the "flat damage buffs" you get in raids arent really flat damage, they are melee dps modifiers.  Meaning that the damage is being added to melee damage currently, which then is being effected.  The only skill i saw that was a true flat damage was jin surge, it added the damage at the very end, the rest added directly to melee damage, which is something they dont even mention in their post.

This is 100% true for solo vs raid, i parsed it last night and i didnt get any funky results.  If i had +600 "flat" damage it was adding 600 to main hand and 300 to off hand.  In raids i can literally take my melee dmg for what i see in the character tab, and calculate all of my combat arts based on that.   There is nothing funky going on and ill prove it tonight with some hardcore parses and numbers.  The issue isnt it being multiplied 11 times per skill its that its being added to melee dmg and then the melee dmg is being adjusted via the combat art.

I never get consistant 50k+ hits (and also don't see how you do that), yet i parse about 40% over the highest sorc due, in whole, to their crappy detaunt, not my "bugged" abilities
Even so i think a 40-50% dmg nerf will change a lot in my eyes 

So I grabbed a 50 monk on test, stripped him naked, documented the resuls apporpriately. 

Stance - Dragon stance (Since it gives only health regen and no damage bonuses)
Wp - Weapons - Identical weapons 139-152
St - Str - 316 (+232.5 Dmg Bonus)
IH - Iron Hand - +200 melee damage
JS - Jin Surge - +364 damage

Note:  These tests were conducted on a L50 monk without Buffs (self buffs, others buffs, guild hall buffs) and completely naked other than the weapons.  The weapons themselves only gave +15 Str and had no other modifiers (such as % dmg). 

Damage Source Wp + St Wp + St + IH Wp + St + Js Wp + St + IH + Js

Main Hand      372 - 387 506 - 520 616 - 629 749 - 763

Off Hand      185 - 193 251 - 260 306 - 315 372 - 381

Dmg Added MH / OH / Total Dmg 134-133 / 66 - 67 / 200 - 200 244 - 242 / 121 - 122 / 365 - 363 377 - 376 / 187 - 188 / 564 - 564

We can clearly see based on these results that Iron Hand (+200 melee damage) is adding +200 damage split amongst the main hand / off hand at approximately a 66% / 33% ratio (about 133 / 66)
We can clearly see based on these results that Jin Surge (+364 Generic Damage) is adding +364 damage split amongst the main hand / off hand at approximately a 66% / 33% ratio.  (about 243 / 121)
We can clearly see based on these results that when Iron Hand and Jin Surge, the additional damage is increased by 564 the total combined of +200 and +364 and is divided at a rate of 66% / 33% (about 376 / 188)

My conclusion is that +damage, regardless of source, is the same (other then what types of damage they affect) and in the case of melee based attacks is added at a rate of approximately 66% to the main hand and 33% off hand.  This includes the sources of +damage known as Iron Hand and Jin Surge.

Every time i test and +damage buff thats not what i see.  I see 100% goes to the main hand and 50% goes to the off hand, every time.  As a whole 66%/33% is accurate in that of the total 300 damage added, 66% is on the main hand.

Ive done this test naked , and with full raid buffs, and i see the exact same thing both times.


***Yes i have jolt/errant/celerity macroed
***Yes i have war/pal buffs (pal only some times)
***I always group with a cleric/bard, and have bear shm buffs


As for that on test, is that new cause this is as of right now on live?
Naked (minus 2 flawless fistwraps of striking)
Str: 357 (+276 dmg)

                                       Main                                     off hand
Wpn:                        139-152 (avg: 145.5)                139-152 (avg: 145.5, 72.75)
wpn+str:                   409 - 423 (avg: 416)                203 - 211 (avg: 207)
Melee - wpn:            270 (97% of str bonus)           134.25 (97% of 0.5*str bonus)
wpn+str+ironhand     622-635 (+212 dmg)              309-317(+106 dmg)
wpn+str+ih+FS          718-731 (+96)                         356-364 (+48)


FS= frenzied symbiot, +86 damage

So as you can see your numbers are vastly different then mine.










So i parsed last night heres my log of just the thousand fist line.

[22:19:27] Your <highlight>Thousand Fists IV</color> hits DREAD LORD MALAZATH for <highlight>50490 (36891+13599)</color> damage.

Your <highlight>Thousand Fists IV</color> hits SENATOR DEMETRIUS for <highlight>52843 (37490+15353)</color> damage.
[22:29:53] Your <highlight>Thundering Fists III</color> hits SENATOR DEMETRIUS for <highlight>61373 (44650+16723)</color> damage.
[22:29:55] Your <highlight>Legendary Fists</color> hits SENATOR DEMETRIUS for <highlight>60904 (43485+17419)</color> damage.
[22:29:58] Your <highlight>Fists of Transcendence</color> hits SENATOR DEMETRIUS for <highlight>62028 (43712+18316)</color> damage.

Thats with errant/jolt celerity each time. 

It was redundant for Fuj to have posted in both spots before checking his facts.  I linked to here because VGplayers Table formats sucks, it's much easier to use the Joomla system which vanguardmonks and vgbards uses to accuractly show data.  I posted the explanation of what the abilities are doing there because that is where talisker posted his thread.  I cross linked the two so that they could both be taken into consideration.