Isn't that just what I said? I contrasted such a Jesus-figure with one who did not do those things, and said that the Jesus-figure you describe would count as a historical Jesus and one that did not do those things would not.

I don't understand. My version just has four elements: being an itinerant preacher, being called "Jesus of Nazareth", being crucified by the Romans, and having his followers begin the Christian movement.

You already conceded there were many itinerant preacher, so that's nothing special that we'd expect documentary evidence about for any specific one of them. You already conceded that the name "Jesus" was commonplace, so there's nothing special about that either. We know as a matter of historical fact that the the Christian movement thought themselves as followers of Jesus of Nazareth. That' s indisputable. So the only thing that's so extraordinary that you expect "documentary evidence" for you to you believe it happened, was that there was a crucifixion of this person? You don't believe crucifixions happened in Judaea, is that it?

What exactly is this extraordinary hypothesis that you disbelieve in without the presence of documentary evidence?

There could be many reasons, but the most obvious possibility is that Paul (or whoever) made up a story with those elements,

And again you can't explain why those elements were inserted. You just don't have an explanation for them if they were fictional, you just call it a mistake on part of the unknown authors and move on.

Cult leaders don't make up stories about fictional people with their own divine missions, they make up stories about their own visions, their own supposed divine missions. Show me a cult leader that ever invented other fictional people to be the messiahs, instead of themselves.

You aren't addressing any of my points, you have just written your bottomline.

I'm still not clear why you assume the zero point of the graph is a real story, as opposed to a made-up story.

That's very simple.

Besides all the arguments I've already given you about none of the story make at all sense as fictional, and goes against everything we know about how religious groups write their stories, there's the plain fact that when asking if a person that's supposed to have lived in <insert century here> existed for real or not. I give significant weight to the beliefs on the subject of the people that lived in his/her time, or as near it as we can get.

I haven't seen "documentary evidence" that Socrates existed. It's just that his contemporaries believed him to exist, and his life story doesn't make sense as a fictional story. Same with Jesus and his own near-contemporaries.