Because when in doubt, just listen to Goldman and do the opposite.
With opinions mixed as to whether or not Jackson Hole will be the forum for Yellen to say something new, many are trying to figure out if it is a buy the rumor and then buy more after the fact event, a buy the rumor sell the fact event, or a do nothing with the rumors and then buy the fact if the USD is actually rallying after the fact event.
And now you know.