The synthetic routing corpus generator puts different-net pads on top of each other (0.28 mm and 0.32 mm overlaps) before routing starts. The harness records input_legal but still counts those boards, so invalid inputs show up as router failures in the metrics.
From the Grok pain-radar digests, Oct 28-29 2026 (Oct 28 8:41 AM ET through Oct 29 early-morning Haitch editions). Verified live 2026-10-29: issue/PR read; title and state confirmed.