Bands were assigned from whole-object bounds, so a rail beside a building
carried the building's height and low cover blocked from above. Each stroke
is now probed with horizontal sightlines across its ink at every 0.1 m up to
40 m; the heights that block at 60% of stations become its bands, structure
set back behind the wall's own face is dropped, and strokes with no geometry
in their corridor keep their previous bands. Recorded reviews, fixtures and
partitions keep their bands on both sides; a lowered piece whose touching
neighbours stayed high is rejected so no notch opens in a solid wall; a top
raised above what the ink footprint itself contains is rejected.

66,790 of 93,129 walls changed, mostly gaining the upper-storey and
overhang bands that the 8 m ceiling had hidden; 8,737 lowered, 326 opened.
The gameplay suite passes apart from the three failures already on the
branch. Split is unchanged.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>