I should have been more clear in my original post:

    The precedent is that corner crossing is illegal and fences to enforce that are ok.

I meant to ask: Are fences around your lot of land legal? I would think, yes, to protected livestock against predators. However, it would be trivial to add a small space at the corner for people to do "corner crossing" between checkerboard public lands.

Next, the PDF is a great share. I am feasting on it now! Page 7 reads:

    Other than these chained-together signs, there were no posts, fending, or building within one-quarter of a more of the corner.

What a laugh! Thank goodness this kind of behaviour is being overruled!

Another good part (pg7 again):

    [T]here is no evidence the Defendants caused any damage to the Plaintiff's property.

On page 9, the photo of A-frame ladder in action is brilliant! The guy looks so hardcore in 100% camo. This is the like the ultimate HN "legal hack". If you position the ladder just right, all four legs will be in public lands.