I believe it would mean he was either ambidextrous, which is uncommon, or right-handed, which I believe is the point, moreso than which hand he wrote with.

If we could determine whether Z was right or left handed generally, then it might be handy* when looking at suspects, where people who knew them might recall which they favored when working with objects. For example, if Bryan said the guy used his right hand when showing him the gun, handing them the rope, and using the knife, and people who knew POI XYZ said the guy was a strict left-hander, then we’re probably looking at different people.

*weak pun.

Right. I get your logic. But, I will give you an example. I shoot right or left-handed. I fight mostly southpaw, but I can fight orthodox. I can use a knife equally well with both hands. In fact, I can use two knives at the same time. But, I can only write with my right hand. So, if you saw me shoot or stab someone, you would have no earthly idea which hand I write with. Now, I get that I’m somewhat of an anomaly (my parents told me that I am naturally left-handed but that the forced me to write only with my right hand). But, I think the principle holds true that its hard to know what hand someone writes with by observing other activities.

However, we do know that there are certain letter formations and writing traits that are characteristic of lefties (smudged text is one that I got from lefty because when the get lazy, their wrist or palm glides over the text they just wrote). So, I would take a handwriting expert’s analysis over what a witness says about what hand Zodiac used for a given action.

I understand your point and you understand mine.

My thought is that if you asked people whether their neighbor, for instance, was right or left handed, you might get 20 times as many people who could recall them favoring one or the other while throwing a ball to their kids, or unscrewing their radiator cap, or one of a million other common activities, as you would finding someone who could recall seeing them writing something.

So, just as we have estimates on Z’s size and age, and can compare POIs and their attributes against them, it would also be nice to know if Z was, generally, a righty or lefty.

And yes, Vegas, you and your situation are unusual in that regard.