I do not like the way it fits in to the rotation. I feel it causes me to energy cap at times, and provides me with more Blackout Kicks than I have the GCDs for, especially during Energizing Brew and Bloodlust. When not in a high energy regen phase it fits in a bit better but as we get more gear, meaning more haste and energy regen as well as more mastery that we wont always be able to reforge out of I am worried that energy capping during mastery procs will be almost completely unavoidable at certain times.
I feel the best solution to this would be to change our mastery completely. I a few ideas currently on what I might like to see as a "new" mastery.
Tiger Power - Mastery could be applied to Tiger Power buff to increase armor penetration with more mastery. This might not be the best idea because a repeat of armor penetration stacking might be a bad thing in PvP.
Tiger Strikes - Mastery here could either increase the chance to proc it, or possibly just increase the damage done by the procs. The problem with an increase to proc chance is procs could overlap each other at higher mastery values.
Blackout Kick (DoT) - Mastery could increase the dmg done by BoK's dot portion. A little more boring than the other two but I am not a big fan of the current state of mastery so I would take it.
If you have more ideas on a new mastery I would love to hear them!