I just tried simming it, and it seems like a loss. Granted I wasn't terribly thorough, but the difference between mastery and our other stats seems pretty large. Here's the gear setup I used for the mastery build (I just picked the highest ilvl piece with mastery on it in most situations, but I did sacrifice a few pieces for the 4 set):
Code:
head=helm_of_the_somber_gaze,id=115556,bonus_id=567
neck=engineers_grounded_gorget,id=113892,bonus_id=567,enchant=75mast
shoulders=mantle_of_the_somber_gaze,id=115559,bonus_id=567
back=cloak_of_delving_secrets,id=113929,bonus_id=567,enchant=100mast
chest=unrendable_wolfhide_robes,id=113951,bonus_id=567
wrists=squires_electroplated_bracers,id=113962,bonus_id=567
hands=handwraps_of_the_somber_gaze,id=115555,bonus_id=567
waist=belt_of_bloody_guts,id=113636,bonus_id=567
legs=legwraps_of_the_somber_gaze,id=115557,bonus_id=567
feet=treads_of_the_dark_hunt,id=113974,bonus_id=567
finger1=unexploded_explosive_shard,id=113877,bonus_id=567,enchant=50mast
finger2=spellbound_solium_band_of_fatal_strikes,id=118302,enchant=50mast
trinket1=meaty_dragonspine_trophy,id=118114,bonus_id=567
trinket2=beating_heart_of_the_mountain,id=113931,bonus_id=567
main_hand=head-lopper_skullscythe,id=119448,bonus_id=567,enchant=mark_of_the_bleeding_hollow
Here's the set I tested it against:
Code:
head=helm_of_the_somber_gaze,id=115556,bonus_id=567
neck=darklight_necklace,id=113865,bonus_id=567,enchant=75mult
shoulders=mantle_of_the_somber_gaze,id=115559,bonus_id=567
back=drape_of_the_dark_hunt,id=113971,bonus_id=567,enchant=100mult
chest=vest_of_the_somber_gaze,id=115558,bonus_id=567
wrists=squires_electroplated_bracers,id=113962,bonus_id=567
hands=treacherous_palms,id=113832,bonus_id=567
waist=girdle_of_unconquered_glory,id=113907,bonus_id=567
legs=legwraps_of_the_somber_gaze,id=115557,bonus_id=567
feet=iron-flecked_sandals,id=119340,bonus_id=567
finger1=unexploded_explosive_shard,id=113877,bonus_id=567,enchant=50mult
finger2=spellbound_solium_band_of_fatal_strikes,id=118302,enchant=50mult
trinket1=meaty_dragonspine_trophy,id=118114,bonus_id=567
trinket2=beating_heart_of_the_mountain,id=113931,bonus_id=567
main_hand=talrak_bloody_skull_of_the_thunderlords,id=113939,bonus_id=567,enchant=mark_of_the_frostwolf
I'm not a simulation guru, but the non-mastery set came out about 7% ahead in both ChiX/Ascension and in Serenity/Brew. The mastery build had ~68% uptime on TEB and the normal one had ~58%. I didn't make any rotational changes between the two, but nothing immediately comes to mind to change. If someone else could make sure I'm not doing something really dumb that would be much appreciated.
Logically there's nothing magical about 100% uptime on TEB. It's not like a haste breakpoint or anything like that. The only relevant number I can think of is 60%, because that means you get a 10 stack for every FoF, but you don't need to stack mastery to get really close to that.