Test 1: the enforced count rose. AM-2, AM-6, AM-9 and AM-11 moved from
unmutatable to red; AM-7's hash clause was re-earned so it is 2/3 rather
than 1/3. Kernel spec->code link 15/18 -> 18/18, names only.
Both denominators are stated. 8 of 14 is 57%, but four rows cannot be
enforced — AM-3 blocked on an artifact, AM-4c withdrawn, AM-5 declared
ungated by the spec, AM-10 withdrawn — so it is 8 of 10 enforceable. The
14 stays the headline and AM-4c stays in it on purpose: a score improved
by deleting the question is not an improvement.
Test 2: one row regressed and was caught. Moving AM-6's gate from debug to
release turned its mutation SURVIVED, because 4,000 black_box iterations
were calibrated against debug's 3.4x headroom and are invisible against
release's 20x. The generalizable finding is that a weak mutation is not a
fixed property of a row — it can become weak when the row's measurement
conditions change, without the row, the mutation or the code being
touched. Final SURVIVED count: 0.
Test 3 is now mechanical rather than asserted. mutation-check gained an
EXPECT-VACUOUS verdict: if a row's expect string appears in PASSING
output, the FA guard would accept any failure at all, so the row is
reported broken rather than red. Final run: 0 vacuous expects across 14
rows. The control exists because the failure happened — my first expect
for AM-2 was "AM-2", which appears in the passing report and would have
accepted a compile error as proof of enforcement.
The cost result is a refutation, not a win. Mechanical share rose to 50%,
the highest ever recorded and above the 38% baseline that motivated
CB-WP-0004. That is not a tooling regression: environment setup and task
closes are still at zero two passes on. It is the other half of CB-WP-0004
T06's finding arriving in force — text patching (45 turns, $13.79) and
orientation (19 turns, $10.97) never had their manual path removed, and a
code-heavy pass is exactly where that spends.
Mean context 493,486 against a 200,000 target, up from 315,170. SessionShape
has stated SS-01..SS-05 since CB-WP-0003 and none has ever been enforced —
the only acceptance-adjacent numbers in this project with no gate at all,
in a pass whose entire subject was ungated numbers.
Numbering corrected: the workplan said CB-EV-0004, which CB-WP-0005
already used. This is CB-EV-0005.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
tegwick
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