I can confirm this. I have the finished Teiwaz of fire path Magic dmg +3 offers a slight boost over HQ staves.. however it seems you only get NQ staff accuracy.
The same probably goes for the Macc+3 version. The boost seems to be 5% better then HQ staffs. But this boosts just one part. Either Magic dmg or Magic accuracy. The great thing for brd is: we have no use for Magic dmg +3. So we just got a more accurate version of a Terra's Staff or Apollo's Staff. Depending on which one you pick. The only thing you need to get this is time.
I am not sure which one I want either:
Teiwaz Macc+3 light based for lullaby and finale? I still need Apollo's Staff for charm then.
Teiwaz Macc+3 earth based for elegy and Lightning Threnody. Would be nice to go /whm instead of /blm for certain HNM fights but I doubt a 5% boost will let me go brd/whm instead of brd/blm.
You still have to keep NQ versions of the elemental staffs because sometimes you want the cure potency or -Physical damage taken.