Repose is a great ability early to mid-game. Most tanks take so much damage early on, so it helps. Has some uses in a few cases at end game too, if you're doing a normal run and the tank is taking damage at an alarming rate. Unfortunately, even if you do make macros, most people will wake them up regardless.
If I'm to be honest, it's not like most black mages even bother to use their CC anyway, so the CC falls on you in most normal cases.