The symmetric ciphers

[Robert J. Hansen]

Quoting Philipp Klaus Krause <pkk at spth.de>:
> But ROT10 and ROT16 fail the condition that breaking them should be
> substancially harder than applying them.

Arguing that "but that's not a real example!" is a nonstarter.  It  
wasn't presented as a real example.  It was presented as a way to  
illuminate the principle involved -- that algorithms can interact with  
each other in ways that diminish the security of both -- without  
needing to break out graduate-level mathematics.