Jeff, as @WarriorIng64 indicates, it's redundant. As for usability, IMO the notification bars are one click too much at all times, but it's a minor issue and on MSO it's considered a non-issue. I believe most MSO users are not interested in usability. It's a pity because with some minor tweaks, StackExchange usability could be more awesome than it already is.

@WarriorIng64, I changed the tag. At the time of writing, I hadn't awarded the bounty (my mistake), however, at this moment the bounty has been awarded and I still see one of the notification bars (I closed the other).