Originally Posted by
Delia
The 200% haste multiplies (not adds) with the haste from gear (and haste from DI and haste from a Spriest if they stay within range), so I'm pretty sure haste would still beat out mastery even with DS as filler.
For instance, if you have 20% haste from gear, you'd get 1.2 x 1.03 x 1.05 x 3 = 3.89 or 289% haste
vs
Say 15% haste from gear would get you 1.15 x 1.03 x 1.05 x 3 = 3.73 or 273% haste
meaning while flying, each percentage point of haste is actually worth about twice as much as it normally would be, effectively doubling its point value, where as using DS as filler does not double mastery's value (though it does increase it)