docs: record uncertainty-over proposition coverage

docs/current-handoff.md

@@ -191,6 +191,15 @@ Experiment 54N tested whether an interpretation disagreement can be judged for m
 - Final question regressed to generic wording (`What outcome would demonstrate enough value to justify launching?`) despite `selectedQuestion.nodeId` remaining the customer-signing node; full proposition preservation therefore remains unproven live.
 - Rationale contamination remained absent.
 
+### 60B.30 `uncertainty over whether` proposition coverage
+
+- 60B.29 exposed one more bounded synonym gap: `Uncertainty over whether...` was not entering the established `whether ...` proposition path.
+- `extractMeaning()` now extends the same description-start normalization to also strip `uncertainty over` before the existing `^whether` proposition extraction check.
+- As a result, `Whether...`, `Unknown whether...`, `Uncertain whether...`, `Uncertainty about whether...`, `Uncertainty regarding whether...`, and `Uncertainty over whether...` now all expose `whether X` before rationale stripping and evidence framing run.
+- Focused deterministic verification passed:
+  - `npx vitest run tests/graph/question-formulator.test.js` → PASS (39/39)
+- **Still unproven live:** the exact 60B.29 `Uncertainty over whether...` customer-signing case through the full end-to-end runtime path on this branch.
+
 ### When This Knowledge-Management Phase Is Complete
 
 Provisional criteria for review (all confirmed met by Experiment 38 cold-start test):

docs/experiment-60b30.md

@@ -0,0 +1,136 @@
+# Experiment 60B.30 — `Uncertainty over whether...` Proposition Coverage
+
+**Branch:** `feature/proposition-prefix-over-v0.32`  
+**Starting HEAD:** `35a5efa80480eb00e69b1004f33e20330fe2434e`  
+**Date:** 2026-08-14  
+**Status:** COMPLETE
+
+## Objective
+
+Close the narrow live coverage gap exposed by 60B.29 by extending the existing bounded proposition-prefix normalization so:
+
+```text
+Uncertainty over whether X...
+```
+
+enters the same `whether ...` proposition-extraction path already used for:
+
+```text
+Whether X...
+Unknown whether X...
+Uncertain whether X...
+Uncertainty about whether X...
+Uncertainty regarding whether X...
+```
+
+## 60B.29 Live Gap
+
+60B.29 preserved the full reasoning chain live but surfaced a new bounded synonym form in the node description:
+
+```text
+Uncertainty over whether the prospective enterprise customer will sign if we launch this year, because their contract accounts for approximately £700,000 of the expected first-year revenue and could materially flip the net-value comparison.
+```
+
+Because `uncertainty over` was not part of the existing normalization boundary, deterministic formulation did not expose:
+
+```text
+whether the prospective enterprise customer will sign if we launch this year
+```
+
+to the established evidence-framed proposition path.
+
+## Exact Normalization Added
+
+Production change was limited to `lib/graph/question-formulator.js`.
+
+Inside `extractMeaning()`, the description-start normalization used before the existing `^whether` proposition check now also strips:
+
+```text
+uncertainty over
+```
+
+case-insensitively.
+
+This means the following bounded forms are now equivalent for proposition extraction:
+
+```text
+Whether X...
+Unknown whether X...
+Uncertain whether X...
+Uncertainty about whether X...
+Uncertainty regarding whether X...
+Uncertainty over whether X...
+```
+
+Each now exposes:
+
+```text
+whether X
+```
+
+before the existing rationale stripping and evidence framing run.
+
+## Exact 60B.29 Deterministic Regression
+
+For:
+
+```text
+label:
+Prospective enterprise customer signing status
+
+description:
+Uncertainty over whether the prospective enterprise customer will sign if we launch this year, because their contract accounts for approximately £700,000 of the expected first-year revenue and could materially flip the net-value comparison.
+```
+
+the deterministic final question is now:
+
+```text
+What evidence would clarify whether the prospective enterprise customer will sign if we launch this year?
+```
+
+The final question excludes:
+
+- `£700,000`
+- `expected first-year revenue`
+- `materially flip`
+- `because their contract`
+
+and the source description remains unchanged.
+
+## Focused Verification
+
+Run exactly as bounded:
+
+```bash
+npx vitest run tests/graph/question-formulator.test.js
+```
+
+Result:
+
+```text
+PASS — 39/39 tests
+```
+
+Focused coverage confirms:
+
+- exact 60B.29 regression passes
+- `Uncertainty over whether...` without rationale uses evidence framing
+- previously-supported prefixes remain unchanged
+- direct interrogatives remain unchanged
+- nominal non-`whether` behaviour remains unchanged
+- source description remains intact
+
+## Preserved Existing Paths
+
+This change did **not**:
+
+- redesign question formulation
+- broaden parsing beyond one explicit uncertainty synonym
+- add domain-specific wording
+- change decision-family routing
+- change question-target selection
+- change graph structure, materiality, schema, provider, or harness behaviour
+
+## What Remains Unproven
+
+Deterministic coverage for `Uncertainty over whether...` is now proven, but the exact full live 60B.29 rerun on this branch remains to be executed.