You can also pray to weather gods, then belief-driven systems are enough. Even permissible nonsense remains nonsense. There are many false compromises where you can "save". Guide rails are precisely there so that the stuff also works without dead calm.
Are you somehow projecting frustration? Or is something with substance and less aggressiveness coming afterwards?
As it is, this general claim is unfortunately a null statement.
So, why are cord-guided venetian blinds nonsense in every situation? It's not as if cord-guided venetian blinds are not used...