See attached picture. The ideal loop filter tags the two end segments (and deducts points) as a non-ideal loop.
Thanks NinjaGreg! This is a bug with the Ideal Loops Objective that we'll have to patch up.
For now, I think this will effect every solution equally, so the max score for the Objective on this puzzle is effectively reduced. We won't close the puzzle, but we apologize for the inconvenience!