I always used it in any primal I was brd on and in any content where we were facing any boss, especially coil. I would watch for Death Sentence and make sure the tank was covered with RoD before DS went off and I would use it when one of the 2 groups were going to be hit with fireballs. If I decided that at one point the tank was taking more dmg than I was comfortable with I would quickly hit RoD to help and continue with my dps and dots. True there were some who didn't use RoD and some who didn't even know what it did and wondered why I would use it on a single target when it was aoe but I would tell them why and what it did and they would say "that makes sense" and "I never thought of that".
Now you can command warriors to do what we did as part of our job.