Fixing this would take all of, what, an hour of a developer's time? You can say it was a (mere) oversight, but it's pretty big fail given they were finally introducing something useful for (non-vampire) pure mages and it just *can't* be that hard to fix. For FSM's sake, the spell 'Thunderbolt' works properly, so why is it hard to make a staff do the same??
I know Beth doesn't bother with fixing glitches in DLC, which is what makes this even more disappointing. Realistically, fixing the staff with the release of DB would have been the only time they were ever going to bother with a fix for this, so now it's basically not gonna happen.