Pretty much just use it when you're running low on TP and need to conserve. You'll do more damage per GCD with the RoH combo and the pacify is often unreliable, particularly if you have other people in the group throwing out debuffs too. Not only are bosses often immune, but there's diminishing returns to consider. I kinda just expect to see it fully resisted these days. So the real draw to the ability is for TP efficiency, and that only becomes a concern late in a long fight where you have no real threat concerns to deal with. I think it's on my 5 key, which is somewhere easy to reach but not part of the main rotation.