Sadly i have tried devastation in off hand and it doesnt hold a candle to striking. The main hand was about the same, but the off hand lost about 20 dps vs jagged fist wrap of striking.
Few things to note about off hand <-> main hand interaction.
1) You only attack once, even if you have 2 different delay weapons.
2) To accomidate for 1), your weapon delays are averaged and this becomes your new delay (although it might be weighted)
3) If equiping a new off hander LOWERS the main hand dmg (attack numbers) then i would venture a guess you probably lowered the average delay of the two weapons by using a faster off hander.
Just as an FYI if you can do it...
I highly recommend a Martial Sword of Frost, martial staff of weakness, and hand wraps of earth touch (when they get earth touch fixed).
I've notice monks in generate seem to proc these effects much more often than other classes. The frost effect is VERY nice, weakness is a great boon for casters, and earth's touch is also extremely nice as well when it actually works which it isn't currently. Nothing like procing earth's touch and getting hit by its 2k+ dot. When earth tough is actually workings, its basically an extra 100 DPS.
Most of these you can quick switch the weapon in and within 2-3 hits will proc, given our attack rate, thats almost instant.
Frost currently lasts 1 hour, dunno if thats a bug or not, but its effectively a 1 hour low damage dot, with -15% spell and melee haste.
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