CB-WP-0015: the two inert clauses, AM-7 scaling and AM-8 N=10

Provenance (tier S, one paragraph in lieu of survey and ADR): the two
clauses mutation-check has reported inert since CB-WP-0005. AM-7's
scaling ratio was held up by a test literally named
replay_100k_events_is_linear_and_fast that computed both throughputs,
printed both, and never divided one by the other. AM-8's N=10 was held
up by a runner that does two.

Both are now red. AM-7 3/3, AM-8 2/2, M-D1-MUT 10/14, and ADR-0005's
>=10-of-14 prediction MET for the first time. Neither was closed by
amending the question away, which was the live risk: the denominator is
unchanged and the four unenforced rows are the four already
unenforceable.

AM-7 needed three estimators. Best-of-N per leg then divide (AM-6's,
correct for a floor on one number) gave 0.581-1.085 on an unchanged
binary; legs back-to-back gave medians 0.931-1.004; legs interleaved at
fold granularity give 0.987/0.991/0.989, and 0.989 under 8-way CPU
contention while absolute throughput fell 4x. The INDETERMINATE guard
demanded unanimity and failed a good measurement over one sample
0.001 under the floor; it now requires a two-thirds majority. The
control that matters: AM-6's constant-cost mutation halves throughput
and leaves this ratio at 0.999x green, so AM-7 is not a second AM-6.

AM-8 kept N=10 because the measurement said so. Perturbing the RNG only
from its fourth construction on: --runs 2 PASSES, --runs 10 fails. A
late-onset divergence is deterministic, not flaky, so it is a control
rather than a coin flip. Ten runs live on one scenario (make am8, ~2s)
rather than all 25 (47s a build). GameKernel 5b records it.

The full run also found AM-4a's own mutation stale since ADR-0008 D3
moved the target 250,000 -> 161,000 in CB-WP-0013 -- reported
HARNESS-BROKEN, no score published. The build-free half of that check
is now a --self-test assertion, so make all catches the next one.

mutation-check clauses may now carry their own verify and mutation, and
then the enforced flag is measured rather than declared; a declaration
disagreeing with its measurement is refused.

make all exits 0.

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

workplans/CB-WP-0015-the-inert-clauses.md

@@ -2,7 +2,7 @@
 id: CB-WP-0015
 kind: product
 title: "The two inert clauses: AM-7 scaling and AM-8 N=10"
-status: todo
+status: done
 ---
 
 # Purpose
@@ -68,7 +68,7 @@ what the mutation says, not on which outcome closes more rows.
 
 ```task
 id: CB-WP-0015-T01
-status: todo
+status: done
 priority: high
 ```
 
@@ -103,11 +103,41 @@ write that up and amend the row, following the precedent AM-4c set in
 `specs/GameKernel.md` §5a — the argument goes in the spec, at tier S,
 with the row retained in the denominator.
 
+**Done 2026-08-02.** `make am7`; AM-7 is now **red, 3/3 clauses**.
+
+The clause is live and no amendment was needed. Measured ratio **0.987 /
+0.991 / 0.989** across three runs against the 0.9 floor, and **0.989 under
+eight-way CPU contention** — the design is flat, as the bounded-state
+analysis predicted, with a few percent of cache cost on the longer log.
+
+**Two estimators were wrong before the third, and both looked
+reasonable.** Best-of-N per leg then divide — AM-6's estimator, correct for
+a floor on one number — gave **0.581 to 1.085** on an unchanged binary.
+Running the legs back-to-back inside one sample gave medians 1.004 /
+0.931 / 0.956: closer, but a 50 ms leg samples a *point* on this machine's
+drift rather than averaging it. Interleaving at fold granularity with 10 M
+events a leg makes the drift common-mode, and it divides out. Absolute
+throughput still swings **11 M – 55 M ev/s**; the ratio does not.
+
+**The INDETERMINATE guard was wrong for the same reason the estimator
+was.** It demanded unanimity. Under contention the median read 0.971 and
+one sample read 0.899 — a thousandth under — and it failed the build; it
+also fired intermittently inside `mutation-check`, which runs this test
+straight after a 50-second rebuild. It now requires a two-thirds majority
+agreeing with the median. A gate that fails when the machine is busy is a
+flake, and a flake gets suppressed rather than fixed.
+
+**The mutation, and the control that matters more.** Making fold cost grow
+with history drives the ratio to **0.751** — red, tight, no straddle.
+AM-6's *constant*-cost mutation halves throughput (28M → 15M ev/s) and
+leaves this ratio at **0.999× — green**. Without that control, "AM-7 goes
+red" would have been consistent with AM-7 being a redundant copy of AM-6.
+
 ## Task: settle AM-8's N, at 10 or at 2, with the argument
 
 ```task
 id: CB-WP-0015-T02
-status: todo
+status: done
 priority: high
 ```
 
@@ -136,11 +166,44 @@ does not change what that mutation catches, that is itself the finding.
 Do not amend the spec silently. If N becomes 2, GameKernel §5 says so and
 says why, in the same shape as §5a.
 
+**Done 2026-08-02.** `make am8`; AM-8 is now **red, 2/2 clauses**.
+`GameKernel.md` §5b records where the ten runs live.
+
+**N stays at 10, and the measurement is why.** The argument above is
+correct as far as it goes — a deterministic divergence shows on run 2
+exactly as reliably as on run 10 — but it is not the whole population.
+Perturbing the RNG only from its **fourth** construction onward, on
+`gr-r06-round-resolve`:
+
+| | result |
+|---|---|
+| `cb-sim --runs 2` | **PASS** |
+| `cb-sim --runs 10` | FAIL — *"run 1 hash … != run 4 hash … (of 10)"* |
+
+A **late-onset** divergence is a real class the double-run structurally
+cannot see, and — the part that makes it usable — it is *deterministic,
+not probabilistic*. So it can be a control rather than a coin flip, and
+the `N=10` clause is now measured by it rather than declared.
+
+The cost objection stands and is answered by placement, not by amendment:
+ten runs across all 25 scenarios would cost **47 s per build** to
+re-answer an answered question, so `make sim` keeps K8's double-run over
+everything and `make am8` runs ten on one scenario in ~2 s. The primary
+defence against the *probabilistic* class is still the `HashMap`/`HashSet`
+deny lint — this row's other clause, already live — and the ten runs are
+defence in depth against that exclusion failing.
+
+Also here: `scenario::run_n`, `cb-sim --runs <n>` (which refuses `n < 2`
+rather than falling back to 2 — a flag that silently degraded would report
+an N=10 result after an N=2 check), and later runs compared to the **first**
+rather than to their predecessor, so a divergence appearing at run 5 and
+persisting cannot hide after run 6.
+
 ## Task: evidence, and what the acceptance table now claims
 
 ```task
 id: CB-WP-0015-T03
-status: todo
+status: done
 priority: high
 ```
 
@@ -164,3 +227,29 @@ Also due here:
 - **Whether the acceptance table still has a PARTIAL row**, and if the
   answer is no, whether that is because both clauses became live or
   because one became a spec amendment.
+
+**Done 2026-08-02.**
+[CB-EV-0013](../evidence/CB-EV-0013-the-inert-clauses.md). `make all`
+exits 0.
+
+- **No PARTIAL rows remain, and neither clause was amended away.** AM-7
+  red 3/3, AM-8 red 2/2. **M-D1-MUT 10/14**, measured, and ADR-0005's
+  standing prediction (≥10 of 14) is **MET for the first time**.
+- **The denominator did not move**, which was the live risk. This pass
+  could have improved its score by deleting a question — amending AM-8's
+  N down to 2, or splitting AM-7's scaling into a fifteenth row — and both
+  were considered and refused. The four unenforced rows are the four that
+  were already unenforceable.
+- **The full run found a third defect: AM-4a's mutation was stale**, still
+  pointing at the 250,000 target ADR-0008 D3 replaced with 161,000. It
+  reported HARNESS-BROKEN and refused to publish a score. The build-free
+  half of that check is now a `--self-test` assertion, so `make all`
+  catches the next one instead of only a full mutation run.
+- **`mutation-check` now measures a claim it used to assert.** A clause
+  may carry its own verify and mutation; then its `enforced` flag is
+  measured and a declaration disagreeing with its measurement is refused.
+  Two clauses carry one, and print as `red*`.
+- **CB-EV-0009's prediction came due**: CB-WP-0014 opened above the SH-1
+  hard line and cost 0.220 $/response against the predicted floor of
+  0.123. Unfalsified, **not confirmed** — there is no control, because no
+  pass has opened below the line since it was made.