Bettye Hardens alleged comment.

Don't know if that is clear enough to see as I can only paste this size photo but the 'B' that comes from the hand of Bettye in signing her name, and that of the 'B' constructed by Zodiac in 'Badlands' are identical.

"You are skeptical somewhat that the Hardens actually solved the three-part 408-symbol cipher."

No. Obviously Don & Bettye were the two that solved the Cipher, of that there is no argument. I suppose I am more suspicious rather than sceptical of their successfully cracking the cipher and wonder whether, given Bettye's comments in the book, if they were somehow involved in the creation of the Cipher in the first place that they then claimed to crack.

But yeah I see your point about Bettye's possible meaning behind the books comments but that's only to a certain degree. Her comment of "I started the Zodiac Case..." could very well be her making reference to her and Don's cracking the initial Cipher. However, she can't say, or has no basis to make the claim that "And I ended it" because she did not, and could not, end Zodiac/The Case. If she's hinting at her having solved the 340 and/or knows by some other means something of who Zodiac was then the obvious question is why not disclose it like you did with the 408?

 To say "I started the Zodiac case, and ended it. When I write the true ending it will shake the Earth" can only imply one thing and that is, she has knowledge of something about this case that others are not privy to and when she decides to tell the public it will shake the Earth.

 Now I know that most may think questioning Don and/or Bettye's extent of involvement in this case is not something that they will give any time to but I am only asking questions because of the way they say they solved the cipher, the fact that the professional code breakers couldn't decipher it, and the comments made by Bettye herself. It is a recognised characteristic of serial killers to interject themselves into their own case and it's investigation, usually under the ruse of being a witness or some other form of benign and somewhat helpful role.

 The Harden's daughter said that her parents achievement in successfully solving the code was made all the more commendable because this was their first ever real attempt to decipher a complex code like that sent by Zodiac. She does state that her mother, Bettye, was extremely interested and fascinated with Graphology and that her Father, Don, did have the book 'Secret and Urgent' by Fletcher Pratt  on his book case for as long as she remembers but no real extensive interest in Ciphers or Cryptography.