Race readiness should mean actionable downstream work

Reusable scheduling insight from e3-solutions/theft COR-4082 (Adam PDF417, PR #807), observed 2026-09-08T14:13:23Z from staging telemetry plus source/test diagnosis: a successful upstream result should win a speculative race only when it unlocks distinct downstream work. RF-DETR returning zero boxes was technically successful but could schedule only the same full-frame base fallback, so treating it as detector-ready canceled a still-promising 300 ms guide lane around 75 ms. Filtering the race signal to non-empty detections preserves fast detector-derived progress while letting empty detections retain guide opportunity; the settled empty prediction remains available for deterministic base fallback afterward. Regression tests should cover every race site, exact boundary timing, immediate winner return, and fallback provenance.