Hi,
personally i like your iteration way.
Question: If i go through all of the direction elements ...
Answer: I use the IEnumerator until .MoveNext() returns
false, so i think i iterate all elements. Inspected the
code already step by step and in the last segment the
distance is 0, like expected, but the name of the waypoint
isn't the last one. direction.waypoint is not the last
waypoint.
Is it normal that the last waypoint isn't referenced?
(Tell me, yes, the direction items reference all waypoints,
no, the last waypoint isn't referenced because it isn't
necessary)

To test i use 6 points. startpoint = endpoint... do me!