ticket(#000008): §12.7 cap-only A/B — cap and reminder help differently

§12.7 captures the 2026-05-03T12-47-23Z cap-only A/B (apply_caps=
True, reminder=False) on the 9-question broad subset.

  Mode      | Baseline | Reminder | Cap-only
  ----------+----------+----------+----------
  JSON SR   |  0.19    |  0.22    |  0.33    ← +14pp
  JSON U    |   7      |   1      |   6      ← reminder dominates
  JSON S    |   5      |   6      |   9      ← cap dominates
  ptr ratio |  0.473   |  0.643   |  0.516
  JSON ratio|  0.524   |  0.735   |  0.643

§10.8 gate MET on JSON mode (+14pp STRICT-rate).

Headline insight: cap and reminder help in DIFFERENT ways.
- Reminder rescues UNGROUNDED → HYBRID (restates citation rule).
- Cap rescues HYBRID → STRICT (forces fewer-but-better claims).

The two are complementary, not redundant. If §12.8 (cap+reminder)
confirms the compound effect, that's the §10.8 trigger to land
Option D as default. Predicted JSON SR ~0.40 if effects compound.

Pointer mode still 0/27 STRICT under cap-only — TOO_MANY_CLAIMS
fires 20× (vs 7× baseline) but pointer-tag failures upstream of
the cap still gate the verdict.

docs/tickets/ticket-000008-broad-quantifier-preflight-guard.md

@@ -1891,7 +1891,7 @@ Empirically:
 Per §10.8 decision tree, A/B sequence with this same broad subset:
 
 - [x] **Reminder only** (apply_caps=False, reminder=True) — §12.6.
-- [ ] **Cap only** (apply_caps=True, reminder=False).
+- [x] **Cap only** (apply_caps=True, reminder=False) — §12.7.
 - [ ] **Cap + reminder** (apply_caps=True, reminder=True).
 
 5pp signal floor per `docs/bench-maxing.md` for default-flip
@@ -1970,3 +1970,77 @@ supported by the data. **But hold the default flip until §12.7
 cap-only and §12.8 cap+reminder cells run** — per §10.8 we need
 to know whether cap+reminder beats reminder-only by ≥5pp before
 defaulting to D vs B.
+
+### 12.7 Cap-only A/B (2026-05-03T12-47-23Z)
+
+Same 9-question broad subset. Policy override:
+`--policy quantifier_guard_apply_caps=true`. Reminder=False.
+
+Three-way comparison against §12.2 baseline and §12.6 reminder-only:
+
+| Mode                    | Baseline       | Reminder-only  | Cap-only      |
+|-------------------------|----------------|----------------|---------------|
+| `quote` strict-rate     | 0.56           | 0.52           | 0.59 (noise)  |
+| `pointer` strict-rate   | 0.00           | 0.00           | 0.00          |
+| **`JSON` strict-rate**  | **0.19**       | **0.22**       | **0.33**      |
+| `pointer` mean ratio    | 0.473          | **0.643**      | 0.516         |
+| `JSON` mean ratio       | 0.524          | **0.735**      | 0.643         |
+
+**JSON-mode verdict distribution:**
+
+| Cell           | STRICT | HYBRID | UNGROUNDED |
+|----------------|--------|--------|------------|
+| Baseline       | 5      | 15     | 7          |
+| Reminder-only  | 6      | 20     | 1          |
+| **Cap-only**   | **9**  | 12     | 6          |
+
+**Headline: cap and reminder help in DIFFERENT ways.**
+
+- **Reminder rescues UNGROUNDED → HYBRID.** JSON UNGROUNDED
+  collapsed 7 → 1 (−22pp). Restating the citation rule keeps the
+  model from giving up.
+- **Cap rescues HYBRID → STRICT.** JSON STRICT jumped 5 → 9
+  (+14pp). Forcing fewer-but-better claims raises the per-claim
+  grounding bar — the model can fully ground 5 claims it couldn't
+  fully ground at 12.
+
+**§10.8 gate verdict — MET on JSON mode.**
+
+The §10.8 rule for cap-only is implicit ("Option A"): if cap
+reduction shifts STRICT/HYBRID/UNGROUNDED distribution by ≥5pp,
+enable Option A.
+
+JSON mode +14pp on STRICT-rate alone clears the floor. Pointer
+mode unchanged at 0/27 (the cap forces TOO_MANY_CLAIMS to fire 20
+times instead of 7, but pointer-tag failures upstream of the cap
+still gate the verdict).
+
+**Pointer-mode violation deltas (cap-only vs baseline):**
+
+| Kind                  | Baseline | Cap-only | Δ        |
+|-----------------------|----------|----------|----------|
+| **TOO_MANY_CLAIMS**   | 7        | **20**   | +186%    |
+| TITLE_MISMATCH        | 10       | 13       | +30%     |
+| NO_EVIDENCE_POINTER   | 9        | 7        | −22%     |
+| CITATION_MISMATCH     | 14       | 15       | +7%      |
+| FORMAT_COLLAPSED      | 2        | 2        | 0        |
+| WARRANT_MISSING       | 4        | 4        | 0        |
+
+Cap firing 20/27 in pointer mode is exactly what we'd expect when
+the cap drops from 12 to 5/8 per intensity. The cap demotes STRICT
+→ HYBRID via TOO_MANY_CLAIMS but doesn't fix pointer-tag discipline.
+
+**Implication for cap+reminder (§12.8):**
+
+The two interventions are **complementary, not redundant**. The
+reminder reduces the UNGROUNDED pool by improving format
+discipline; the cap promotes HYBRID to STRICT by tightening
+per-claim grounding requirements. If §12.8 confirms the compound
+effect, that's the §10.8 trigger to land Option D as default.
+
+Predicted §12.8 outcome (n=3, 9 questions):
+
+- JSON STRICT-rate: 9 + N more → 0.33 + ~5pp = ~0.40 (if effects compound)
+- JSON UNGROUNDED: 1 (already low; reminder dominates this metric)
+- Pointer STRICT-rate: still 0/27 (neither knob fixes pointer-tag
+  discipline at this sample size)