The tooltips are the same as when you get free shouts when you enter the battleground.

Reduces the power cost of spells and abilities by 100%.


If i can spam shout before it starts, and everyone else can buff...

and then everyone else can buff after they res, and i can't...


its gotta be a bug, or something not intended.

As the tooltips state this is working correctly. If you disagree please post in the suggestions or PVP forums.