Document July 2026 tuning conclusions in Strategy Status

Record every tested-and-confirmed knob (ATR trail, regime overlay, lookback,
cutoff x book, sizing, FIP tie-breaker) so the sweep is not repeated on the
same snapshot, including the inverse-vol mis-attribution warning and the
universe-level fip_id lead. Prune the done items from the next-experiments
list.

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

README.md

@@ -85,6 +85,24 @@ Live-ranking note: the backtest ranks residual momentum and volatility inside ea
 
 Parity guard (July 2026): the portfolio monitor's **Production** row replays the *runtime* configuration — the live activation gate (`qualified` flag) and the Admin exit policy (mode / ATR multiplier / hold days) — so tuning the strategy in Admin is reflected in the next backtest run instead of silently diverging. Constants defined on both sides (exit defaults, trail width, the 80/20 ordering weights, the promoted cutoff) are pinned by `tests/unit/test_prod_strategy_parity.py`, and the ordering weights are single-sourced from `momentum_service`.
 
+### Tuned and confirmed — do not retest without new data (July 2026)
+
+A systematic single-variable sweep (offline prod snapshot, production gate/rank/exit, 2022-06 → 2026-07 plus disjoint 2022–23 / 2024–26 folds) confirmed **every** production setting. Retesting these against the same ~4-year snapshot is wasted compute and invites overfitting; revisit only with meaningfully new data (longer history or broader universe).
+
+| Knob tested | Verdict | Evidence |
+|---|---|---|
+| ATR trail multiple {1.5–4.0} | **Keep 3.0** | Return+Sharpe peak; ≤2.0 whipsaws out the momentum right tail; ≥2.5 is a plateau |
+| SPY 200d-MA regime overlay (block entries / go flat) | **Reject** | Halves return (315%→138%) with zero drawdown benefit — the ATR trail already manages downside, and the filter blocks the recovery-phase entries that make the money |
+| Momentum lookback: 6-1, 3-1, 12-7 (Novy-Marx), composites | **Keep residual 12-1** | 6-1/3-1 rank-IC ≈ 0; 12-7 IC 0.045 / t 1.58 — weaker than residual 12-1 (0.055 / t 1.98) |
+| Selection cutoff {70, 75, 85, 90} × book size {10, 15, 20} | **Keep 80 × 10** | Monotonically worse in both directions from 80; the 10-slot cap never binds (<10 concurrent) |
+| Position sizing: equal-weight, inverse-vol, risk-% sweep | **Keep 1% fixed-fractional** | See the inverse-vol warning below |
+| FIP path-smoothness as an in-book tie-breaker/filter | **Reject** (but see the lead below) | Non-monotonic across FIP quintiles within the qualified set; either half of a median split underperforms the full book — thinning the entry stream costs more compounding than the tilt returns |
+
+Two findings future sessions must not re-litigate:
+
+- **The "inverse-vol sizing win" (July 2026) was mis-attributed — do not resurrect.** The diagnostic sized `notional = equity × 1% / vol_6m`, and the 20% notional cap bound on 95% of entries, so it actually measured "~5 positions × 20% notional each" — a concentration/risk-appetite bump economically equivalent to raising risk to 1.5%, not vol-managed sizing. Genuine inverse-vol sizing (risk budget × median-vol/vol) cuts max drawdown to −18.2% but costs ~58pp total return at flat Sharpe: a risk-preference trade, not edge.
+- **`fip_id` — Da/Gurun/Warachka information discreteness over the 12-1 formation window — is the strongest cross-sectional signal measured on this universe: IC −0.045, t = −2.91, correct sign (continuous-information winners outperform).** It clears the iron-rule bar in isolation but does not improve this book (the momentum gate already captures the effect in-sample). It is the prime ranking/gate candidate **if the universe broadens** (e.g. `nasdaq_all`).
+
 ### The iron rule for strategy changes
 
 A signal earns its way into selection **only** through the factor harness:
@@ -97,11 +115,9 @@ Corollaries: never let an unvalidated score gate setups; the outcome evaluator m
 
 ### Highest-value next experiments (in order)
 
-1. **Forward monitor the promoted strategy** — the production UI now behaves like a portfolio monitor for the current strategy, with selectable lookbacks and SPY comparison.
-2. **Trailing-stop sensitivity** — locally compare 2.5x, 3x, and 3.5x ATR trails before changing the promoted 3x default.
-3. **Capacity check** — retest residual/high-vol 80/20 with a max-15 weekly book cap; promote only if it improves drawdown or trade quality without costing too much CAGR.
-4. **Signal context snapshots** — accumulate point-in-time composite/sentiment/fundamental context for every new setup so the discretionary overlay can be tested forward-only.
-5. **More breadth, not more history** — widening the ranked universe (e.g. `nasdaq_all`) strengthens each week's cross-section and the IC t-stat, even if only the top slice is traded. (Deeper history was considered and declined.)
+1. **Forward monitor the promoted strategy** — the production UI now behaves like a portfolio monitor for the current strategy, with selectable lookbacks and SPY comparison. Forward paper-trade months are the only evidence the snapshot cannot provide; the July 2026 tuning pass closed every in-sample lead. (Trailing-stop sensitivity and the max-15 capacity check are done — see the tuning table above.)
+2. **Signal context snapshots** — accumulate point-in-time composite/sentiment/fundamental context for every new setup so the discretionary overlay can be tested forward-only.
+3. **More breadth, not more history** — widening the ranked universe (e.g. `nasdaq_all`) strengthens each week's cross-section and the IC t-stat, even if only the top slice is traded. Now doubly motivated: it is also where the strong `fip_id` signal (see tuning findings) could become tradeable. (Deeper history was considered and declined.)
 
 ## Key Use Cases