Yes, that fold, but specifically that leading point of it. Often the back can have a reference point, like having the edge of the wing meet the bottom rear corn

Yes, that fold, but specifically that leading point of it. Often the back can have a reference point, like having the edge of the wing meet the bottom rear corner of the fuselage. But yeah, the fold in general is often more arbitrary. But not really; you would try to fold a plane as consistently as possible, so something like 'begin the fold 1/8" from the tip of the nose' isn't arbitrary at all. Similarly, you often don't want to fold right to a crease, as it can cause bunching. It's often a better idea to leave a mm or so of extra space for inward folds. Doesn't make the design less pure or anything though.