Of course, the main question now is whether the decryption makes sense. Here’s the ciphertext:
As can be seen, this letter doesn’t look like an encrypted text at all. So, if there is a secret message contained in this text, it must be hidden with a steganographic technique. The Daily News article doesn’t provide any details, it just mentions “a system of letters and numbers”. This means that we can’t check whether Sherwood’s codebreaking makes sense.
Even if Sherwood’s deciphering is correct and if it refers to afore-mentioned Robert Rackstraw, there are serious doubts about this new finding. As far as I know, there is no proof that this letter was really written by Cooper. It only contains information that was available in the press.
According to the Wikipedia article about Dan Cooper, Sherwood has “deciphered” other letters allegedly sent by Cooper before. The details might be given in a TV documentation I haven’t watched yet. Here is a radio report by the same producer:
Apparently, the new decipherment will be covered in an another TV documentary about the Cooper case, which will air in the near future.
Does it make sense?
To be honest, this story about the alleged Cooper decipherments doesn’t look very sound to me. It has probably been made up to promote a series of TV documentaries. I would be surprised if the letter shown above really contains a hidden message.
If you know more about this story, e.g. if you find a text hidden in the above letter, please let me know.
Further reading: The Zodiac Killer code is solved – at least in this new movie