BLM can save the flares for when people start guarding and continue after, I've ran down tons of people while flarespamming when I have a drk ally pulling them in, speaking from experience, it is rediculously powerfull and you can do it from a safer distance than astro, which is the biggest plus.

That and it's a mass cc if you do some freezes ontop of it so you can snare them all after the guards go down as the ice stacks stay and continue to pile up even if guarded, so insta aoe bind/stun on enemy raid to allow other aoe to keep raining hell on em.