I have to imagine it procs combat meditation, talents and all of that. But if it doesn't it's just gonna be garbage. It does seem like if it procs from Effusive Anima Accelerator (EAA?), it will be busted for all three specs. Every 10 seconds you're chopping 20 seconds (maybe) off the cooldown of Divine Toll. So you basically just spam it all day long.
Honestly not sure what Blizzard is thinking with this one. Surely they considered the interactions between two brand new spells. Even if the legendary gets nerfed to 20% or 30% damage, it will still probably be the play with Mikanikos because you will be a walking Divine Toll pulse.