diff --git a/decisions/decisions.md b/decisions/decisions.md
index 7b2c9dd..90fe484 100644
--- a/decisions/decisions.md
+++ b/decisions/decisions.md
@@ -785,3 +785,126 @@ decided_by: Bernd Worsch
 created: '2026-09-06T06:07:34.017316Z'
 updated: '2026-09-06T06:07:34.017316Z'
 ```
+
+## Context
+
+`GH-WP-0003-T04`. v0.7 §9.5 states the maturity half of the boundary — *"Given the
+same criteria and the same evidence it MUST return the same level; that determinism
+is what makes it an Engine rather than an opinion"*, and *"A criterion that cannot be
+evaluated by rule is not yet a criterion."* It does not state the posture half.
+
+Gate House had proposed drawing the line on volatility: posture is fast-moving,
+maturity is slow. `kings-guard` answered `KG-IN-0003` with a proposed revision
+(`KG-DEC-2026-002`, argued in `kings-guard/docs/PostureMaturityBoundary.md`) rejecting
+that line and offering recomputability instead. The commentary was also sent to
+`maturity-engine`.
+
+The concern behind the original question stands and is why the line has to be exact:
+a second grading authority would be the same shape of mistake as a second decision
+point, and §6 says it would arrive the same way — gradually, each time for a good
+local reason.
+
+## Decision
+
+**The boundary is recomputability, not volatility.**
+
+> Given the same criteria and the same evidence, recompute. If you MUST get the same
+> answer, it is maturity and it belongs in an engine. If you CANNOT promise the same
+> answer, it is posture and it belongs in Staff.
+
+The volatility line is withdrawn. `kings-guard`'s argument against it is accepted in
+full: volatility is an observation about how a value has behaved, not a definition of
+what it is. It fails at both edges — a maturity criterion moves fast when evidence
+lands in a burst, and a posture sits unchanged for months on a healthy subject — and,
+more seriously, it *describes* the two categories without *partitioning* them. Every
+case it does not obviously cover becomes an argument, and arguments at a boundary are
+the mechanism §6 exists to prevent.
+
+Recomputability is not a new rule. It is §9.5's own determinism clause pointed at the
+one boundary where it had not been pointed, which is why it can be adopted without
+enlarging the standard. §9.5 already states the maturity half; the posture half is its
+mirror, and the pair partitions: **a criterion that cannot be evaluated by rule is not
+yet a criterion; a judgment that can be evaluated by rule is not posture — it is a
+criterion sitting in the wrong repository.**
+
+### The addition — criteria must be grounded
+
+Adopted with one clause `kings-guard` did not propose, and the reason is the loophole
+their own framing opens.
+
+Recomputability is assessed **over the stated criteria**. That makes it mechanical,
+which is its virtue, and it also makes it satisfiable in form by the thing it exists
+to exclude. Any judgment can be made to look recomputable by writing a criterion that
+dereferences it: *"level 2 iff the reviewer marked the control adequate"* is perfectly
+deterministic — recompute it and you get the same answer every time — and it has
+smuggled an opinion into an engine wearing a rule's clothes. The engine would then be
+grading, deterministically, on someone's judgment, which is precisely the second
+grading authority the boundary is drawn to prevent.
+
+Therefore:
+
+> **A criterion MUST bottom out in evidence about the subject, not in another party's
+> conclusion about the subject.** A recorded judgment may be evidence *that the
+> judgment was made* — a fact with an issuer and a timestamp. It MUST NOT be evidence
+> *that the thing judged is so*.
+
+This is the same distinction §9.6 draws between what an archive proves and what it is
+read as proving, and the same one this repository applies to `valid_now` in
+`GH-DEC-2026-005`: a summary predicate is a fact about the issuer's evaluation, not a
+substitute for the evaluation. Without the clause the test is mechanical and
+circumventable; with it, the test is mechanical and the circumvention is itself
+checkable.
+
+### Consequences carried
+
+The three `kings-guard` names are adopted as stated.
+
+1. **The migration direction is permanent.** Anything called posture that turns out to
+   be recomputable moves to `maturity-engine` as a criterion; anything in
+   `maturity-engine` that needs judgment is not yet a criterion and moves back to
+   Staff. The boundary maintains itself under change because the test applies to each
+   item rather than to the category.
+2. **Two authorities cannot grade the same subject property**, because a property is
+   either recomputable or it is not, and that fact does not depend on which repository
+   claims it. The failure becomes structurally prevented rather than conventionally
+   avoided.
+3. **Capability readiness MUST NOT be an input to posture.** Readiness is
+   deterministic; posture is not; feeding one into the other would make posture partly
+   recomputable and blur the boundary from the `kings-guard` side. Volunteered by
+   `kings-guard` as a constraint on itself and accepted as normative.
+
+Consequence 3 also answers the second half of `KG-IN-0003`: tracking kings-guard's
+own gaps in `maturity-engine` creates no incident-time dependency, because posture
+evaluation never consults readiness. The dependency would exist only if the mistake
+consequence 3 forbids had already been made.
+
+### The limit is recorded, not resolved
+
+`kings-guard` flagged, against its own proposal, that *"the same evidence"* is not
+well defined anywhere in the estate, so until §17's request-claim and gap-record
+schemas exist, recomputability is a thought experiment rather than a check. That is
+recorded in the statute alongside the test rather than left in the commentary. A
+boundary that is correct but not yet mechanically checkable does beat one that is
+checkable and wrong — but a reader is entitled to know which of the two they are
+holding. It makes §17 load-bearing for this rule.
+
+The caution is also recorded: *"posture"* has the drift profile *"control plane"* had
+— it sounds specific and quietly absorbs whatever sits next to it. §8 exists because
+the estate has been bitten by exactly that, and this repository described itself as a
+control plane before the re-cut. The recomputability test is a defence against that
+drift because it can be applied to a candidate *before* the word is stretched to cover
+it. `kings-guard` asked to be held to it rather than trusted about it, and that is the
+standing it gets.
+
+No change to §8's three-way split and no §4 catalog change. Posture stays
+non-deterministic and stays Staff; the test explains why, which is what was missing.
+
+## Reversal
+
+Revert if the grounding clause proves to exclude criteria the estate needs — that is,
+if a legitimate maturity criterion cannot be expressed without dereferencing a
+judgment. The falsifier is a concrete criterion, not an argument that one might exist.
+The likely candidates are human-attested controls (a policy was reviewed, a drill was
+run); the expected resolution is that the *attestation event* is the evidence and the
+criterion grades on its existence, freshness, and issuer rather than on its verdict.
+If that resolution does not hold for some real criterion, this clause is wrong.
diff --git a/workplans/GH-WP-0003-statute-v08-amendment-set.md b/workplans/GH-WP-0003-statute-v08-amendment-set.md
index cee5c94..19ec79f 100644
--- a/workplans/GH-WP-0003-statute-v08-amendment-set.md
+++ b/workplans/GH-WP-0003-statute-v08-amendment-set.md
@@ -106,10 +106,15 @@ volatility describes the two things without partitioning them, and every case it
 not obviously cover becomes an argument at exactly the boundary §6 says must not be
 open to argument.
 
-Assess and dispose. If adopted, it carries a constraint kings-guard has already
-accepted — capability readiness MUST NOT be an input to posture — and an honest
-limit: "the same evidence" is not yet well defined estate-wide, which makes §17
-load-bearing for the test.
+Disposed as `GH-DEC-2026-007`: **adopted**, with one added clause. Recomputability
+is assessed over the stated criteria, so a criterion that dereferences a judgment
+("level 2 iff the reviewer marked it adequate") is deterministic in form and
+inferential in substance. A criterion MUST therefore bottom out in evidence about the
+subject, not in another party's conclusion about it. All three kings-guard
+consequences are carried, including the constraint they volunteered against
+themselves — capability readiness MUST NOT be an input to posture — and their honest
+limit, that "the same evidence" is undefined until §17, is recorded in the statute
+beside the test rather than left in the commentary.
 
 ```task
 id: GH-WP-0003-T05