Phase 47 renumber: blind-champion adjudication (was duplicate Phase 46); register blind4/blind3 cv variants

The blind4 writeup was swept into 4e17cd1 with a colliding Phase 46 header.
Renumbered to 47 per cross-session coordination. cv.py gains the rejected
blind4/blind3 variants with the verdict inline so the port cannot be
re-attempted by inspection.

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

EXPERIMENTS.md

@@ -2369,7 +2369,10 @@ forward-reading of the split file that phase 43(a) verified and declined.
 
 Standing champion: **3c7b883 at 1661.45**. Deadline 2026-08-23.
 
-## Phase 46 - the blind champion itself, as a whole: REJECTED (lineage fully adjudicated)
+## Phase 47 - the blind champion itself, as a whole: REJECTED (lineage fully adjudicated)
+
+(Numbered out of order: written before the phase-46 commit landed from the
+parallel session; the work predates it, the number does not.)
 
 Question (user, 2026-08-22): the blind-repo multi-agent loop's shared champion
 (`9a969a6a7dfe.py`, blind full-40 1566.7) - reusable here? The headline number

batteryswap_example/cv.py

@@ -327,9 +327,23 @@ def _v_last_only(t):
     return ['v_last']
 
 
+def _blind4(t):
+    # The blind-repo champion's EXACT feature set as a REPLACEMENT ranker
+    # (9a969a6a7dfe: last_voltage/vmin7/n_obs/vrel -> our columns). Phase 47:
+    # real head-ordering gain at fixed N (static N=8 +27 [+7,+47]) but the
+    # planner converts it to ZERO extra catches (290 vs 291 count-matched)
+    # and +79/origin cost via cruder day placement. REJECTED. blind3 shows
+    # vrel is not load-bearing - the effect is the small set itself.
+    return ['v_last', 'v_min_7', 'n_30', 'vrel']
+
+
+def _blind3(t):
+    return ['v_last', 'v_min_7', 'n_30']
+
+
 VARIANTS = {'base': _base, 'zone': _zone, 'vcorr': _vcorr, 'vrel': _vrel,
             'vrel_only': _vrel_only, 'vmin7_only': _vmin7_only,
-            'v_last_only': _v_last_only}
+            'v_last_only': _v_last_only, 'blind4': _blind4, 'blind3': _blind3}
 
 ABLATION = ('base', 'vrel_only', 'vmin7_only', 'vrel', 'v_last_only')