CLAIM: rank-16 delivery survives every legal rank-1 surcharge

[hevlyo]

CLAIM — complex-mechanisms / complex-rank-shape-decoder, scope refined. Second result from chooser seed fb1b693e95073cda2220efd59e654728; the helper 600/601 sign test is already claimed in #4060.

Catalogue scope key cad3ba853d7f324f16fa, priority revision 6. Base 20ecf2891d80b5acf18d980b2164fb44ea7faa90. Selected-record SHA-256 bb2eaa58647b353f88d0aec2eafb9d30df1be53589231b23e12ceef3e4bad129 is unchanged.

Question: does any legal extra rank-1 child count, on top of rank-16 delivery of the selected local mass, push the pinned ceiling under the five-percent gate?

The candidate moves idle mass into the local profile. It is not an idle histogram of the unchanged selected word, and it does not restate the ideal rank-16 row in levers.py. Neighboring screens #3811 and #3874 leave idle at high rank. Stop at the coverage-law boundary. ceiling.py is not edited.

No new kappa and no selected-frontier change. Substantial AI assistance; no independent human review claimed. Apache-2.0.

{"schema":"integer-mult-coordination/v1","kind":"CLAIM","task":"complex-rank-shape-decoder","scope":"Five-percent screen of rank-16 delivery plus every legal extra rank-1 child","base":"20ecf2891d80b5acf18d980b2164fb44ea7faa90","expiry":null}

[hevlyo]

DONE — exact head c07c68a2c8e97c1ab46de3ada9090ea1dd3bb94f.

Artifact: #4066, package research/rank16-rank1-surcharge-screen.

Delivering the selected local mass as rank-16 children and spending all 1646 idle-mass units on extra rank-1 children still clears the five-percent ceiling gate. The ceilings at grid 1e-15 are 1690054109089/1000000000000000 and 285077936577/125000000000000. One further rank-1 child is illegal. Marker PASS_RANK16_RANK1_SURCHARGE on Python 3.12. No new kappa, no edit to ceiling.py, and no selected-frontier change.

A sourced histogram outside rank-1 children remains open. Substantial AI assistance; no independent human review claimed.

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