Measure keyboard continuation and navigation feedback

Assistant: codex
Assistant-Model: gpt-6-astra
Assistant-Session: 01a0cffe-206f-7323-89d3-b20ca4cf4bf9

research/evolution/ledger.json

@@ -373,6 +373,43 @@
         "cost_usd": null
       },
       "supersedes": []
+    },
+    {
+      "id": "LEARN-0012",
+      "date": "2026-09-27",
+      "recording": "prospective",
+      "stream": "F",
+      "comparison_group": "F-navigation-focus-v1",
+      "protocol_ref": "research/evolution/cycles/2026-09-27-navigation-focus.md",
+      "question": "Does enhanced route replacement need explicit continuation and feedback policy that respects changed focus ownership?",
+      "previous_belief": "Native controls alone do not establish enhanced focus/feedback semantics; delayed responses should respect focus moved to another surviving task. Modal return is not automatically route continuation.",
+      "conclusion": "Corroborated in 22 cases: raw same-ID link focus survives but this fragment contract leaves stale title and silent failure; authored heading/status policy works and preserves newer search focus. No AT speech or universal heading policy established.",
+      "disposition": "corroboration",
+      "affected_patterns": [
+        "CAND-0010",
+        "CAND-0016"
+      ],
+      "evidence": [
+        "research/reviews/NavigationFocusExperiment.md",
+        "research/experiments/navigation-history/focus-result.json",
+        "research/evolution/cycles/2026-09-27-navigation-focus-effort.json"
+      ],
+      "remaining_uncertainty": [
+        "Author-model DOM evidence, no human/AT validation or independent recurrence.",
+        "Delayed history focus, competing requests, delayed scripts and interrupted enhancement remain open."
+      ],
+      "reviewer": {
+        "name": "Codex",
+        "role": "author-model",
+        "independent_human": false
+      },
+      "effort": {
+        "research_minutes": 5.138,
+        "execution_minutes": 0.525,
+        "reported_tokens": null,
+        "cost_usd": null
+      },
+      "supersedes": []
     }
   ]
 }