Anyone have an explanation...

...as to why Staves only deal half damage? I feel like people could get really creative with healers now that Skill Inheriting is in the game, but Staves dealing half damage is holding them back from potentially being a great offensive and defensive unit.
Did classes with staves ever deal half damage with their magic (or whatever weapon they could use along with staves)? I know that units in Heroes use two separate staves, so "power is shared" is probably not the answer.
Anyone have any ideas?