Perhaps a Guy like Z who was possibly a latent homosexual, or a guy like Ross(who according to Allan may have been A-Sexual),may come across as feminine in nature as far as their writing. Regardless of the tone, or anybody's interpretation, the state's top writing expert said Z wrote it, and it was "unquestionably" the work of Zodiac. There's only two possibilities. One, Sherwood was Correct and Z wrote it. Or two, he was wrong and Z did not write it, and then all Riverside bets are off.
But again, and I know I will not convert anybody here (you know who you are

) let's take the Bates case writings as a whole:
*Desktop linked to Zodiac by State writing expert, and backed up by Traveller1st. Now Trav is certainly not a documents examiner, but his profession & ability allows him to demonstrate and highlight some very striking similarities between confirmed Z letters, and the desktop.
*The Bates case, like the Z case, has a Guy demanding the letters get published. He also writes that he "did make that call", another similarity to Z, calling police after the crime.
*Confession letter similarity also shows link to Z in choice of words, same misspelling of TWICH/TWITCH, and use of the word SHALL that Z was so fond of. And to you skeptics that say the word 'SHALL' is pretty common, I dare you to tell me you have used that word in a sentence verbally or on paper in the last 10 years(not counting Zodiac related). Simply put, it
ain't a common word! Unless you are a writer using it in a Book, or a lawyer filling out some legal mumbo jumbo, that word is not used very much in the USA today, nor was it back in 1969. Here's a nice long thread about the word SHALL-
http://en.wikipedia.org/wiki/Shall_and_will*Confession letter mailed 30 days after attack, and Bates had to die letters mailed 6 months after attack, Z mailed letter to Belli one year after LHR, in both Bates & Z cases, we see letters mailed on the anniversaries of attacks.
*Bates letters had little symbols on them that, whether you believe they are Z's are not, resemble Z's/
*Also, while not solid proof, let's consider 'ZODE' for a second. A Guy in 1963 to 1965, in nearby San Bernardino who admits to calling himself, ZODIAC,(6 years before Z used it) and could be heard saying "this is the Zodiac speaking", is it not the least bit possible that Zodiac stole that persona and that exact saying from Zode after encountering Zode, or knowing Zode by his nickname, or hearing about Zode thru a mutual Friend. Let's face it, if ZODE really called himself Zodiac, and used the phrase "this is the zodiac speaking" in 1964, then we would almost have to assume that Zodiac stole that from Zode in some way, wouldn't we?
Again, it's more than just the desktop, it's all of the writings, and the habits of the writer, that in my opinion, give it away that Z did the writing.