I did a bit of testing on some weak enemies, and I found that if I used it close range on an enemy that remained stationary, they'd generally get hit by multiple projectiles which could add up to some so-so damage. But if they started moving around a bit, then they would likely only be hit by one or maybe two projectiles at most.
Also, I couldn't get it to work very well from any sort of long range or during situations where I was at a higher elevation than the enemy. Manual aiming also seems to be completely ineffective.
Then there's the problem if there's a ceiling or a wall nearby in that all the projectiles can just collide with it.
I'm thinking maybe something like the stray demon might be an appropriate target for this spell, but I haven't tried it on him. I still don't think it would out perform more conventional spells though, and would likely need to be cast pretty close up.
Definitely a candidate for one of the worst spells in the game.