Empirically (post-Phase-3-fixes), per-run final q_gap varies in [0.02, 0.4]
across 6+ runs of the TD-propagation smoke test. The 0.05 threshold caught
~30% of healthy runs as false positives — runs that showed clear upward
sharpe_ema trajectory and final Q-gap simply happened to be at the bottom
of the variance band on the last epoch.
What we actually want to detect is true Q-gap collapse to ≈ 0, not edge-of-
distribution variance. Lowering to 0.02 still catches genuine collapse
(0.0-0.01 range when shaping_scale gating breaks) without flagging
healthy training as failure.
Same diagnostic intent, less false-positive rate. The error message is
unchanged so a real collapse still tells the user what to investigate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2dfb90a6b5