Blizzard added a new macro fuction (exclamation point). It is used to turn on stuff (that is toggleable) and not to turn it off, no matter what. I used this on my hunters when some of them would have an aspect on and some wouldn't. So when I mashed the aspect key, some that had it would turn it off and others would turn theirs on. Crap, not what I wanted. So:

/cast !Aspect of the Hawk

Should turn it on and not turn it off. You can put it in a castsequence if you want also.