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B47: Does B34's criterion discriminate, or return each edge's own m_e? #614

Description

@NGL321

Part of #532. Opened by B42 (#605)'s resolution, which found B40 (#603)'s arm-4 falsifier had fired and been scored on a statistic that could not see it.

Question

Does B34's criterion discriminate, or does it return each edge's own m_e dressed as a reading?

Why this is a ticket

B40 carried the flat bundle as arm 4, a falsifier, stated as: "if holonomy cannot fail then the count reads full width everywhere and carves nothing." It reported the falsifier did not fire, on the grounds that the counts still spread — std 1.2–1.5, 6–7 distinct values, two seeds.

Full width is m_e, and m_e is not a constant. Wide edges on this surface run 10–16. So a criterion that simply returns each edge's own width reproduces exactly the spread the widths already have, and any statistic taken over the counts alone scores it as discriminating. B42 re-ran the falsifier on a bundle that is genuinely flat (identification 0.0000 through the mask and ADR-0032's band, where B40's arm 4 was 0.0386) and compared the count to m_e edge for edge (b42_mirror.py, reserve_p12 seed 42, threshold 0.9):

surface count == m_e mean shortfall below full width
trained control 0 / 104 (0%) −13.8
B40 arm 4 68 / 104 (65%) −1.1
B42 reserved frame 69 / 104 (66%) −1.0

The trained surface genuinely selects — it discards ~14 of ~14 directions. On the flat bundle the criterion keeps ~93% of full width and discards about one. That is the falsifier's own antecedent, met.

What this must settle

  1. Whether B34's decision survives. B34 decided holonomy-count is a usable carve criterion. It decided that against a falsifier the record says did not fire. B34 is not reopened by this ticket — this indicts the evidence, and the map's shape is that a resolved ticket advises rather than rescopes. What is decided here is whether the criterion needs replacing, repairing, or nothing.
  2. What the right null is. The spread statistic cannot separate carving pressure from the width distribution echoing back. Any replacement must be scored against a surface where the answer is known — count − m_e is one candidate and was enough to expose this, but it is not obviously the right one, and normalising by how many cycles an edge reads was already on B41's list.
  3. What this does to the clauses B34 already had. Only the floor acts, and it leaks at √1.25 because pruning concentrates the band's norm; 90 of 194 wide edges are true bridges with no cycle to read at all. If the count is a mirror on cycle-bearing edges too, the criterion acts nowhere.

Why it blocks B46

B46 (#613) designs a gate around this criterion. Designing a gate for a mirror is work that could be wasted, and B42's own resolution enlarged B46's subject to the node stalk mask as well.

Notes

Instruments on worktree-b42-flat-bundle-605 (7e02410): b42_mirror.py is the edge-for-edge comparison, b42_falsifier.py re-runs B40's scoring beside it, b42_reserve.py builds the genuinely flat surface. Threshold 0.9; B40 reported at 0.8/0.9/0.95 and nothing here rests on the value.

Plan, don't do.

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    wayfinder:grillingWayfinder ticket: resolved by conversation (HITL)

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