With raiding now public for everyone, for those who haven’t figured it out yet, it is worth while to spend shards (as Destro with rain of fire) to get the Diabolic Ritual started before the pull. If you are lucky, the raid will pull the boss while you have a demon ready to summon. You can have some crazy pulls if you have the Shivarra or Pit Lord right on pull. But I hate that the hero spec is designed in a way that its main power is either so delayed, or at the whim of your raid pulling regardless what the state of your ritual is.
Using this… quirk will separate locks on parses quite a bit, but I hate that this is a quirk and not that you just start with the Overlord available on your first shard consumption after your last Diabolic Ritual fell off.