It does come in handy though if a few cursed enemies go down in the same round, for example, being able mass-curse a bunch of minions, then set up the boss with the Daily the next round, and I think attack bonuses are the best. But I agree it would be meh if one had to add it to the roll beforehand.
I think I'm going to run it, after the roll, like the Wand of Accuracy. otherwise, that would be next to useless too.