I have experienced the same thing as the above poster and faguely remember having an issue where something that should have worked showed "the desired affect is not present".
Also, last night channel hatred started showing like it had a 15 minute cooldown. I was able to use it correctly, even when the 15 minute timer expired, but that was freaking me out a bit. This was on corellia, where i started running into several issues (retaliate issue has been ongoing).
My point is that maybe it is part of that UI bug. If you start getting the message, but the icon is lit, just do nothing but spam it to see if maybe the UI is showing you the wrong thing. As for the twirl animation, I've found that stopping everything, so as to reset the animation and GCD, seems to let retaliate work correctly. And then it seems to be good for awhile. I know it's difficult seeing as we have to spam a ton, but just give it a second to breathe, and it'll catch up
Edit: To add a bit, I have mapped my second bar to be Shift+1,2,3.... etc. Sometimes, I'll be holding shift and spamming #3, for instance, and it will trigger the abilities on #3 AND Shift+3. I would theorize that it might be polling the keyboard twice, which could explain this, the above problems, and possibly other things.