CW could possibly be an incredibly nice, but, encounter based Trinket.. but as the progress goes, for now it's just a huge pain if it proccs in the worst few seconds of the fight.
Tested it myself, after i got it, on Nef, Chimaeron, Maloriak, Conclave and Council and either of those fights it procced just in those few worse-case seconds where i got halfblown up and received a full ragebar for pretty much doing nothing..
Let's pinpoint it a bit:
BWD:
Omnitron, due to the high amount of Movement and target switches, the possibility of a procc in a bad situation is very likely BUT if you get a procc when you have to AoE those slimes and don't have a fixate on you it cooould be pretty awesome.
Magmaw, a nice not sooooo much Enviromentaldmg-Encounter where CW could be nice, but if you get his lavaspit AoE in a procc your ragebar is full ;D - for the Head-Phase it's possible that it's a veeeryy huge trinket.
Maloriak, a Procc in the Dark-Phase would be Awesome.. but(!) if you're specced properly to do High-AoEdmg you're Arms.. and for that, haste just sucks, for fury it would be very nice to have a procc in those AoE-Phases.
Atramedes, here it just sucks.. had proccs myself right about where he would fly high in the sky and laughed at me trying to jump as high as he flies to attack him furthermore :<.
Chimaeron, this is the best encounter for being a pain in the ass.. for seconds you get a totally free full ragebar and in the next you get a -75% Hit debuff which just sucks up all your rage if you don't pay attention, CW just sucks here

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Nefarian, nawww.. HoR/LtS are pretty much the nicest trinkets you could have for this fight.. due to his AE, the Tailwhips of Onyxia, the High-AoE in Phase2 and the possibility of constantly crushing his badass tail is a nice Ragebar.
BoT:
Halfus, i can't give that much of a big test here, due to the fact that i have to tank on it :<, but i think.. the first half of the fight, where you bomb down pretty much everything and it's your goal to avoid those pesky little fires it would be nice. However in the second half of the fight it's a little twisted.. a procc right before his Roar fucks it up, a procc right after it gets you a pretty nice income of rage.
Valiona&Theralion, the incoming rage of the Debuff-dispel is just enough to get me my full attention on pressing CS,BT,RB & slam for it's full potential. i don't really think that Crushing Weight would outweight (funny wordplay here) the other possible Trinkets here.
Council, it's sooooo not cool if you get a procc right before you have to move (this encounter just sucks :<) for the various amounts of times.
Cho'Gall, you get a pretty decent Rage income throughout the fight because of his AE, allthough in the last Phase it could be very interesting to get procs while bombing the Eyes.
Tot4W:
Conclave, naw.. really? hopping out and in on the plattforms while getting proccs in a transition just made me cry a little bit
Al'Akir, too much Enviromental Rage income for that it could near as good as we want it to be.
Feel free to add something or flame me if i've gone too far ;D