Toter Winkel is for field of vision what Blind Spot is like for flashy surfaces - both obstruct clearly visible areas. T. W. spreads its mirroring wings to let objects disappear. The really dangerous variant is the metaphorical T.W. - societies ignoring threats, because the could shatter the self image.
How to fight it
Install more mirrors than T.W. can possibly cover with its wings. But... remember, mirrors have a monster class of their own. I say: Trust your eyes (most of the time) and be aware that there are areas obstructed. Always remember that other people will not be aware of T.W. and might run you over. If you talk openly about society threating mishaps, be prepared to be shunned, even if you're right. You know the drill already probably.gab