ARCADIA-Studio/harness/experiments/scc-placement-20260925/final-review.md

SCC checkpoint final claim and archive review

Reviewed the current results.md and immutable evidence archive for tested source 2426d286483ab0445663221cd6010a3dadb89a97. Verdict: no blocking finding for this experimental checkpoint. This is evidence/claim acceptance, not production Arrange or native usability acceptance.

Verified facts

• Independently opened the ZIP and checked every member against manifest bytes and SHA256, exact membership and uniqueness, plus ZIP CRC readback (testzip). All 168 members pass. Archive: 6,041,259 bytes; SHA256 fbf40882ed807a1b40db8b3b9b9c846b060db02cbcc60611c18f9620c1fd59c9.
• Both run receipts bind unchanged before/after inputs, correct source pins, eight successful bounded children with no timeout, and exact captured stdout/stderr sizes/hashes. Both route-control byte streams hash to 9a31a676f23dea2f41daec39497f569d68231fa0fd66e5a1a476be97d5d61ac2.
• Independently matched all 14 complete results-table rows against archived Arrange-reset controls and final candidate metrics, including crossings, raw shared length, all three label counts and rounded area ratios. The bipartite, folded, workshop and two-container regressions are disclosed, not hidden behind sparse-case gains.
• Compared all raw input Projects across runs: unchanged. All 13 previously supported complete candidate objects remain exactly equal. The original two-container Final Rust projection differs from intended node geometry rejection is retained; run02 supports that case. All 14 emitted repeat and JSON/source roundtrip checks pass. These emitted checks are correctly distinguished from independently retained repeated full Projects, which are not serialized.
• Gate receipts/logs support source 2426d286's 8 example tests, strict Clippy and optimized build (24–26); source 4dd764fa's 5 tests/Clippy/build (21–23); earlier packing tests; and the retained gate20 exit101 needless_range_loop failure. All gate input inventories report unchanged. No whole-workspace claim is made.

Interpretation and limits

The transfer explanation agrees with the source review and independently derived run01 failure: preserve unchanged effective expanded minima only for qualifying position-exact, noncollapsed nodes that would otherwise shrink, then require one exact final projection. This restores the intended 308×446 parents without changing SCC packing/order/gaps. The unchanged 13 candidate objects strengthen this attribution; the newly supported two-container result still has 164 sharing and one label/node collision, so the correction is not presented as a quality improvement.

The quality verdict is proportionate. Sparse coherent SCCs remove the dominant shared corridor, while residual label conflicts, folded retrace, relation-ID-dependent routing and area costs remain. The evidence supports keeping the structural hypothesis and conducting a bounded next experiment; it does not establish engineer traceability, general lane separation, glyph readability or product acceptance. Proposed external-neighbor sibling ordering should preserve the SCC witness and the fixed full-corpus comparison; its benefit remains unverified.

Archive contents include both runs, failed gates, frozen five-case inputs, controls, scripts and independent reviews. Source is identified by commit; binaries are intentionally excluded but their capture hashes remain. Repository-relative build/CLI examples are suitable reproduction entry points after obtaining that source and locked dependencies. Archived supervisor scripts/receipts retain machine-local paths and Windows environment assumptions: they are provenance, not an automatically portable runner. Short observed runtimes are not performance guarantees; the work counter is weighted. Linux, native workflows, command/history integration, dormant-route translation and State-header coverage remain explicitly outside this checkpoint.

Minor optional wording: “failed flat lead-clearance repair” could read “flat lead-clearance repair rejected on readability grounds”; that earlier repair did remove the targeted lead incompatibility. The surrounding linked results and current non-adoption verdict make this nonblocking.

Review method: read-only archive/JSON/log/source-review inspection and offline comparisons. No compiler, router, GUI or test process rerun. No source/archive changes. Publication remains unconfirmed until parent obtains Gitea success and readback.