[split] Diplomatic ciphers

[ReneZ]

By considering sequences of characters mapping to individual letters it is perfectly possible to provide a much large number of mappings.
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Another possibility I like less is that it could be a diplomatic cipher with anagrams, so breaking the positional structure.

The first point is true, but both points are *not* in line with how diplomatic ciphers were designed.

It is like JKP suggested. 'Atypical' would really have to mean 'not at all''.