Separate S/R detector tests from primary R:R policy

docs/research/sr-levels-and-exits.md

@@ -436,6 +436,17 @@ calls `scripts/compare_sr_variants.py` to produce the paired cohort CSV and JSON
 > the test period. The simulator now treats `BACKTEST_ENTRY_END` as an inclusive
 > entry bound and truncates the calendar after the final position can resolve.
 
+The isolated `rr_aligned_control` validation also failed (Sharpe 2.78 to 1.32,
+CAGR 73.3% to 33.1%, drawdown 11.7% to 18.4%). The live 1.5 primary-selection
+behavior is therefore frozen: although it predates the 2.0 activation gate, it
+acts as a useful selectivity mechanism. The final detector matrix holds that
+behavior constant and varies only detection/zone policy:
+
+- `rewrite_legacy_primary`
+- `soft_zones_legacy_primary`
+- `confirmed_rounds_legacy_primary`
+- `gate_v2_legacy_primary`
+
 The post-2024 interval has informed earlier research, so this is validation rather
 than a pristine holdout; do not sweep variants on it. No deployment follows
 automatically. A lower validation Sharpe or higher drawdown remains a no-ship