If you get a message, which you want to report and block whilst in WvW, especially EotM (Edge of the Mists) it disables your ability to steer in any direction. This is not a problem on wvw—-but on EotM a death sentence. You have either the choice of stop running (kinda obvious I know) and lose touch with the zerg, or chance that you can do it before running over a cliff.
(Did not report this as a bug, as i cant see it as being as one—-just kinda frustrating)