I think the 6.5.2 (page 284) and 6.7 Implementation Guide documentation, Chapter 8, page 283 contains an error in figure 212: Navigation Relationships. I think the node above the circled “Self” node should be labeled as “Parent” and not “Anc”.
It’s a small detail, and maybe both are correct, but it helped me when I was constucting our left navigation macro.
It’s not an error, although I can see your confusion. The node you are talking about represents all ancestors (all nodes in the direct line between the SELF and the ROOT). The PARENT is the adjacent or nearest ancestor in this line. The text that accompanies the graphic explains this detail.
If we get additional feedback on this graphic, we’ll look at it again, but the current graphic represents the best balance we were able to develop between adequate detail, complexity, and size.