[Cryptography] Feedback welcome on an idea

[Grant Schultz]

I have written up an idea (abstract below) for a high-security 
symmetric-key cipher allowing for manual decryption, i.e., without 
requiring a computer.  What distinguishes it is the ability to encrypt 
multiple messages in the same ciphertext.  If caught, one can reveal a 
decoy message instead of the real one.  Encryption does require a 
computer however, which limits its applicability to a very few situations.

Having said that, it was an enjoyable exercise.  If any are curious and 
would like to see the full PDF and comment on it, just let me know a 
good place to send/post it.

Thanks in advance.

G. Schultz

Abstract:  With key logging trojans and other malware in the wild, and 
operating systems being too complex to protect against government 
surveillance, it is necessary to have high-security ciphers which can be 
used without the aid of a computer.  Some proposals in this area include 
Solitaire [1] and Handycipher [2]. The cipher described here further 
explores this space by introducing deniability.