I started to reply to a question by
@Joy_Division in a post by
@Asayre
I began writing to answer his question which was essentially how does one get and apply some of the common formulas for damage you see. I began explaining that and ended up explaining when and where one should use Juli vs Twice Born Star. Also, I refute the common myth that "Twice Born is better for trials than is Juli since it benifits more from war horn." This is clearly false on its surface (warhorn is enchanced by crit chance and diminished by crit damage due to diminishing returns). I go further and explain why, in fact, there's no reasonable situation where you will get more dps from Twice Born Star than Julionos after a war horn is sounded (even though you often do before one is sounded). Also of note, at its base TBS gives better dps for all classes except for the magika templar (there Juli outperforms TBS, but only after the major sorcery buff is applied) and DKS who use a destro staff get better DPS with Juli while DKS with duel wield get better dps with a TBS. I begin explaining where the formulas come from. I'm too lazy to rewrite things, so things are still worded as if this was placed in the original post. If you already know or don't care where the common formulas come from simply skip to the last section of this post.
Are you asking where the formulas come from or how he's applying them? He explain the former well, the latter (except for the mit formulas) are easy to derive once you know that the increases in you damage are linear in the both magika and spell damage, i.e. you can figure out how much damage you do for any of those values if you just know what happens at two points. In practice, this means the damage of any abiltiy under the same conditions (i.e. with same wep trait, either with or without major sorcery) is of the form
Damage of thing = a * Spell Damage + b * Magika
(i.e. there isn't something funky like Magika^2 showing up anywhere). Here's where you actually have to leave the theory world behind and find out what a and b are for a given ability. Well, since we're only interested in increase, you can assume one of the numbers is 1, he (and any normal person) takes b = 1 (otherwise you're looking at numbers less than 1 ... ick).
Damage of thing / b = a/b * Spell Damage + Magika.
Playing with this for a bit in practice you see the surprising fact that a/b is a constant for any ability (.. well, nearly ... I assume the differences are due to ZOS rounding errors) and is roughly 10.5 (i.e. have incorrectly been using 10.4 in the past).
So
Damage of thing / b = 10.5 * Spell Damage + Magika = 10.5 s +m
(where m and s are magika and spell damage).
This means that adding 2 points of spell damage improves any ability in the game by the same amount that adding 21 magika does (... so close to 10 ZOS, why ... why??). So if yo uwant to find out how much more damage of a thing does after improving your spell damage by say, 100, you have
Damage increase as %=
(Damage of thing after/b - Damage of thing before/b)/(Damage of thing before) =
[(10.5*(s+100)+m) - (10.5*s +m)]/(10.5*s+m)=10.5*100/(10.5*s+m)
where, as promised, our friendly (and unknown) b has canceled out. Plug in your s and m if you want .. I have s=3000 and m=45000 typically, so for me, 21/1430 = 0.0147 -> 1.47% improvement. This means, without a doubt, that with these stats if I add 100 spell damage (and without having major sorcery up) my attacks will do 1.47% more damage. With major sorcery up you change the scale factor of 10.5 to 10.5*1.2 (he uses 1.25 for some reason ..) Plugging and chugging shows we end up with a 1.62% improvement now (this is because major sorcery improves spell damage and not magika damage, so spell damage makes up more of your "Pool" as a percentage then it did before, which is unfortunate since it means one needs to do two calculations for these sort of things instead of 1).
The other main formula, (1+crit % * crit mod), takes a bit of algebra, and not very intuitive (it says, for one thing, the two have exactly the same effect on your average damage), and the initial step is to use
Total damage of a given number of tests on average = (1-c) *Number of Tests *Base Damage of thing + c* Number of Tests*R*Base Damage of thing
where c is your crit percentage (hence 1-c is your non crit %) and R is your crit ratio, i.e. damage of a crit divided by damage of a non-crit. That formula should be clear (just think of, say, 10 tests of which c of them crit and (1-c) of them do not). Rewrite R=1+r, so r is (when mult by 100) a percent improvement of crits vs non crits, divide by the Number of Tests (you're looking for an average after all) and by the base damage giving, on average, how much more damage an attack does than it's base giving
(1-c)+c*(1+r)= 1-c +c+c*r=1+c*r. This means if you do 53 attacks which do 100 damage when they don't crit, then, on average you'll end up doing a grand total of (1+c*r)*53*100 damage. (Of course if either c or r are zero, you end up getting no bonus from crit damage so the number is just 53*100.)
(Here's where I get to the subject of the post)
(Here's a different application from what he used in his examples ... )
So how much does Julionos improve your DPS (this is a harder one since it involves both improvements of the first type (i.e. magika and spell damage) and improvements of the second type (spell critical)? I'm going to ignore the magika improvement from Juli since magika gets scaled up, and I'm too lazy to look up how. With some algebra you can see it's via
%Change in DPS via Jul=
(1+299*10.5*1.2/(10.5*1.2*s+m))* ( 1+ 0.06*r/ (1+c*r)) -1 =
(1 + % Change via Juli from spell d) * (1+ % Change via Juli from crit) -1
which is just a reflection of the multiplicative nature of adding spell damage then crit (or the other way around).
How about TBS? (Again, we can leave off magika, and we are justified in this if we want to compare them) is
%Change in DPS via TBS=0.183*c/(1+c*r),
(where I'm assuming the shadow has been added to the thief which is typical since it's easier to get r higher than c.) This formula is easier than the one for the Julionos set since there's only one type of change going on here, crit damage (the r value). (It sucks for comparitive purposes that there's the -1 showing up for Juli and not for TBS, but such is life).
If you want to have some "fun" copy and paste the code
(1+(299*10.5*1.2)/(10.5*1.2*s+m))* ( 1+ 0.06*r/ (1+c*R))-1-0.183*c/(1+c*r)
@r=0.50,c=0.57,m=40000,s=2600
into
http://www.mathpapa.com/algebra-calculator.html to see that for a typical dk with duel wield swords, TBS gives 0.3% more dps than Juli, but when you swap to your destro bar (typically dropping your s to 2200) you end up getting 0.048% (no, i'm not missing a decimal place) using Juli! Contrary to the "myth" that more crit damage means you should use TBS (or equivalently when using TBS one should be stacking crit damage) for a templar (whose only real difference is to improve r from 0.5 to 0.6) you get 0.3% more DPS using Juli. Of course these numbers are soooo small you might as well use TBS since it gives you the added health.
Also note using these formulas that it's impossible with any reasonable numbers to have more DPS with TBS after a warhorn has sounded. Even a sorc (which has the highest base magika and spell damage and small r value) with no points in elfborn (why would a sorc not have any points in Elfborn!?!) gets about 1% more dps with Juli after a war horn is sounded while getting more with the other set, TBS, before (of course as a sorc, you should have points in Elfborn, which moves Juli and TBS into nearly a tie for the sorc, I use Juli only because I don't feel obliged there to have all divines on my gear). I'm not sure where the rumor that TBS is better for trials since it goes well with warhorn started, but it's quite false (maybe for other things, but not for war horn!). It's like an 8 foot tall super skinny dude wishing he were taller.
PC/Mac NA server. Cast, in order of appearance (got one of everything):
Samwell Slayer Stam NB AD Stormproof
Samantha Tarly Stam Sorc DC FC
The Sawmell Tarly Tank DK EP Stormproof
Tamwell Sarly Mgk Temp AD FC
Covenant Blues Mgk DK EP Stormproof
Samwell Tardy Mgk Sorc AD FC
Stam Tarly Stam Temp AD Stormproof
Samwelf Tarly Mgk NB DC FC
Stamwell Tarly Stam DK DC FC
Maester Samwell Heal Temp DC
Samara Tarly Tank NB EP
Sam Mfing Tarly Mule Sorc EP
Warden of HTarly. Mgk. Ward AD FC
Lord Tarly Stam Ward. DC. Still lowbie