Expertise after 6.5%

Although Expertise is still a great stat once you have reached the "soft" cap of 6.5% (knocks dodge off the table) it is less effective at increasing survivability than dodge/stam and therefore shouldn't be gemmed for if you get the 6.5% from gear alone.

Now the maths....

1% increase to avoidance = 1% less physical damage over time

1% increase to expertise reduces the chance a boss will parry you by 1%
However the boss parrying you will increase his swing speed for the next hit by 40%
Therefore +1% expertise only reduces damage over time by 0.4% AND this is MELEE only not all physical attacks (ie. special boss moves)

1% expertise costs 32.8 expertise points
1% dodge costs ~37 dodge points diminishing when dodge is at 20%

So, in a situation where you have a red gem socket you can choose +16 expertise or 16 dodge

[+16 expertise] gem = (16/32. = 0.487% expertise = (0.487x40%) = 0.195% less white melee damage

whereas

[+16 dodge] gem = (16/37) = 0.432% dodge = 0.432% less all melee damage

Dodge gem (at~20% dodge) gives over twice the survivability compared to expertise against white attacks and moreso as it protects against special attacks

A far better gem then +16 expertise would be +8dodge/+12stam as that gives slightly better avoidance and +12 stam for free!!

Of course expertise also helps with threat but I think it is fairly obvious that dodge/stam gem wins hands down

im so glad that we have another avid theorycrafter in the guild !
i dont feel so alone! hehe

thanks for this Richard, its really usefull to know, especially considering my alt is a pallytank !
thankfully without gemming for expertise im almost softcapped anyway gogo Glyph !
although now, i shall be removing the two gems i have giving me expertise and replacih something better, dodge/stam probs

but yep! really usefull, and not just for warrior tanks!

I think an important thing to note is the fact that dodge is useful against special attacks whereas parry only affects the damage from normal "white" melee swings.

For example on Patchwerk the Hateful Strike tanks will not take any more damage whatsoever if the boss parries every attack but dodge will reduce damage

So the more damage a boss does from special abilities the better dodge is over parry ontop of the %s above

I think the maths is correct but if it is wrong please inform me if you think overwise

Dodge remains the best for survivability per point until it costs over 70dodge rating per 1% dodge. I don't know the diminishing return formula but I believe this to be around 28% dodge. Even then it still defends against special attacks whereas parry doesn't