Ok this is a tough one! (I think)

[enbee]

At what point does Expertise rating or hitrating become more valuable then spelldamage for threat output, for instance http://www.wowhead.com/?item=32263 vs http://www.wowhead.com/?item=30995 if the paladin has let's say.. 400 spelldamage before equipping either of the items.

I've been wondering about which one of those 2 to choose for bosstanking, as I won't have 4xt6 bonus either way, so unless t6 legs drasticly outdo praetorians in the threat departement they're not worth it to wear unless it's for the t6 setbonus which is massive ofcourse, it's stam and slightly higher avoidance vs (supposed) tps increase here..

Other good items that can be used to compare are http://www.wowhead.com/?item=33473 vs http://www.wowhead.com/?item=30991 or http://www.wowhead.com/?item=30123

http://www.wowhead.com/?item=33516
vs http://www.wowhead.com/?item=32279

etc

I'm gonna try and figure it out myself later, but I figured I'd post something about it here first, since some people here are far more experienced with theorycrafting/numbercrunching then me :p

[Arthaal]

According to theorycraft by Dorvan done here: http://maintankadin.failsafedesign.com/ ... php?t=3678

Expertise rating: Here the same assumptions will be used as with hit rating.

1 expertise is -.25% dodge/parry (.5% combined), which provides a .35*(.005/(1-.27)) ~= .24% increase in threat generation. 3.94 expertise rating = 1 expertise, so each point of expertise rating provides a ~.061% threat increase. In other words, 1 expertise rating = 1 spell damage at about 825 tps

[enbee]

I should've done a search, fail.