NICK_VNV's original post is a little hard to understand. There are 8 images (some duplicates), although as I am composing this I see only 4 images (strange... ). And it is part bug report and part feature request. But, FWIW, the bug NICK_VNV has noticed does exist (see the image with 4 separate grey line segments). My hunch: looking for the '_furthestapart' points does not work for entities with more than two intersections with the temporary polyline.