Well that probably has something to do with your gemming and stat priorities. You should get an addon called "reforge lite" it will basically make sure you hit caps for you so you don't have to do any calculations. You are currently WAY over hit cap, so some of that hit could be reforged.
You also don't appear to be "going" for any particular stat. At your progression level I would suggest (after hit/exp caps) going straight parry. Definitely get rid of those stam gems.
Helm - go Parry/Stam
Shoulders - 2x flashing (parry) gems
Cloak - Parry
Chest - 3x parry gems
bracers - parry
Gloves - 3x parry gems
Belt - 3x parry gems
Legs - this one is kind of a toss up, these days I'd actually lean towards 2x parry/crit gems or parry/dodge, but you have enough ilevel you can probably just ignore the stam socket bonus and just go 2x straight parry here again.
Rings - parry in both
Feet - parry
Then configure reforge lite to hit your hit/exp caps then have parry be the next highest priority, then dodge, then mastery.
If you are dying a lot with this and don't have a lot of survivability, then re-do your gear and go mastery (after hit/expertise caps). I'm my experience though unless you're vastly undergeared for the content you're doing, you don't get to a boss that requires this until about H-Siegecrafter25 man.
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