There are more clue,s in the form of a map. Showing where the zodiac letters were mailed from and dropped in mailboxes within San Fransisco. This pattern of driving North of the city changed with the Stein cabby attack. Did he get Noticed by Somebody close to him..?
Do you have a link to that map?
I have a working theory that Fred Manalli may have known the Zodiac and because Manalli had a background in literature that he may have recognized his friend's traits and handwriting as the Zodiacs. Manalli worked in San Quentin as an English teacher. It is possible Fred Manalli may have been framed for the Santa Rosa Hitchhiker Crimes. He was killed in an automobile accident. Sadistic drawings of an SRHM victim were found in a search.
The reason why the Zodiac escaped attention is because of who he was.
I believe Zodiac was likely law enforcement.
Disclaimer: I don't think JJD is Zodiac for a whole pile of reasons. However, he can be helpful.
VREARONS (Visalia Ransacker/East Area Rapist/Original Night Stalker) was a cop working 9-5. All the limitations put on LE (law enforcement) and military for that guy evaporate just like they did for Russel Williams also. Basically working 9-5 is not mutually exclusive with working as LE or being in the military.
So if there is evidence pointing at LE, then what is it?
It's the red herrings that appeal to me most and they are also in the VREARONS case. Zodiac is painting himself as a cop-hating villain who can't even spell simple words. So we are supposed to believe in this uneducated, cop hater who is hiding the shadows with a cloak and dagger. So what should we do with that?
Find the Zodiac in the opposite like we can with VREARONS. You know what? It works. The Zodiac investigation has also looked at cops and the military. So there is another clue for us.
Ferrin thought the Zodiac was a cop. So did Mageau and his witness statement includes that Ferrin thought he was a cop. Not some guy she knew or anything like that for this second car encounter. That is why Mageau had his ID out. So that's two Zodiac targets, one who survived, who thought he was a cop. One VREARONS target thought she felt a police belt on him.
The Zodiac uses ruse words like 'pig' which was also used by Joseph James DeAngelo as VREARONS to misdirect.
Zodiac understood cut-off techniques.
Zodiac understood jurisdictional problems and exploited them. He understood switching up m.o. helped him. VREARONS did the same.
Zodiac knew fireworks would delay police responses to gunshots.
Zodiac knew how to escape mostly without being seen. EARONS also knew his escape routes.
Zodiac understood ballistic reports and the first letters are like them.
Zodiac made phone calls. So did EARONS.
Zodiac ordered Hartnell and Shepard to their knees and then went rear just like an arrest. VREARONS had figured out ways to subdue and tie up also.
Zodiac understood that saliva on envelope seals could be used to identify blood type. VREARONS started taking away evidence with him as ONS.
Zodiac uses terminology in his letters associated with LE commands. VREARONS also did this verbally.
Zodiac used his flashlight to blind Ferrin and Mageau. VREARONS also did this.
Zodiac 'reports'. VREARONS asked his targets to report things to law enforcement for him.
Zodiac was calm around LE when they showed up and got away. VREARONS also got away several times from LE including the FBI.
Zodiac jumped into Presideo Heights according to news reports. VREARONS jumped fences.
Zodiac seemed to avoid stakeouts at Vallejo. So did VREARONS. It is believed he has inside knowledge and a police radio.
Zodiac wrote a letter about how he would never blow up a police station and then he said in the next letter he would kill a cop. I think he contradicted himself because he maybe thought his sympathy was too revealing.
The tight-clustered groups of shells on the ground meaning he holds his position before firing. Moves and stops and shoots some more. That's training. VREARONS was very effective at shooting to kill also.
I also believe if we include the non-canonical Zodiac crimes that we shall find the Zodiac leaves his victims to face down if he interacts with them. I think that also speaks to training. Having them on their front and approaching from the rear. Especially at Lake Berryessa.
So I think with everything we learned about BTK and VREARONS that the Zodiac fits the same sort of association with LE in the air. I would also add LISK to that list of four.
Nothing is concrete about what the Zodiac's profession is but things lean towards military experience first and then possibly some connection with LE after.