Well, it’s been a couple of weeks since patch 6.1 dropped and I can say I haven’t once specced out of Beast Mastery the entire time, and I’m loving it. I don’t know what it is, but I just have more fun playing it. Survival is still strong but it was becoming stale for me. What I like about BM is all of the opportunities to stack cooldowns and trinkets. Focus Fire has turned into its own little mini-game, with a ton of variables to take into account rather than the old method of simply using it when the button flashed.
I feel like having so much DPS potential built into Focus Fire has added an entire new dimension to the spec that rewards you for proper decision making. There is a downside with the RNG component, but that probably helps keep it balanced. If gaining Frenzy stacks was more predictable, it’s possible that Focus Fire wouldn’t be able to have the same power level. And to be honest, the awesome feeling I get when I have a pull with good Frenzy stacks outweighs the pulls where I have bad luck. I actually grin when I get good RNG as I play Beast Mastery. I never did that with survival.
In the first paragraph I said I don’t know what it is, but I guess I just answered my own question.