*
The thing is, if you create some links on a page, and there are links on the pages they link to, and links on the pages those links link to, you have a tree.
The original page is a node, and several branches branch from it.
If you follow one of those branches, it takes you to a node, and several branches branch from it. If you follow one of those branches, it takes you to a node ... and so on and on it goes.
Now go back and back and back, and you will arrive again at the first node.
From there you can go out along a different branch, to a node, and from there out some branch, to a node, and from there out some branch ... and now you are on some branch which, in the geometry of the tree, is quite distant from the first branch, that you got to by going out another branch from the first node.
These two branches, which are quite distant in the geometry of the tree, are, in effect, very close together. You could link from one to another, and they would be instantaneously connected. But the geometry of the tree in some sense requires that you not do that. To get from one distant branch to another distant branch you ought to navigate back through the tree to the node where both these distant branches originate ... so, down one branch, from some little, distant branch, to that node, then out another branch to the little, distant branch you want to visit next.
In a very short time I can navigate to any page on my site, here ... in my tree ... it's really true. It's true I may have to click lots of times - that I often do - but it turns out clicking many times does not take a lot of time.
I think it's a kind of evidence that, if you have navigated to this page from a home page, you can use the back button to navigate back to the home page: the browser, Chrome, has automatically recorded all the information you need to do that. And, of course, from there, you can navigate to anywhere in the tree ... and very quickly.
Some additional notes.
*
