Looking at the change made recently to the Spiritual Shine of Defilers, I'm thinking that the equivalent Mystic ability is probably supposed to be raid wide as well.
The description indicates that it works on "allies" which in a raid setting should include all members of the raid. The pet casts "beneficial spells" for 20 seconds which as best I can tell are just tiny heals of 150 to 200 at adept III, correct me if I'm wrong. I don't think we'd get any imbalance from this pet working raid wide (in the heal radius around the pet).
Currently, again correct me if I'm wrong, nobody uses this spell at all at 80.