---
name: mutation-proof-does-not-validate-a-green
description: "Mutation-proving shows a cell CAN fail; it does not show its green MEANS anything — able-to-fail and green-is-meaningful are independent properties, both burned in one day (v0.65.0 respin arc, 2026-08-29)."
metadata: 
  node_type: memory
  type: project
  originSessionId: ffecabec-8000-44d0-ae77-bf3aaf8c4615
  modified: 2026-08-29T04:49:54.602Z
---

**The rule (deployah's formulation, ratified by doyle at the CONDUIT respin):** a cell earns
"able to fail" from mutation cycles; it earns "its green is meaningful" only from the green being
FORCED by the mechanism under test rather than permitted by an incidental one. Passing the first
test does not confer the second.

**Both halves measured in one arc:**
- First head: leg that COULD NOT FAIL (vacuous arms — no cell drove the broken kinds; units
  synthesized rows; treqs green on tags). Cost: full respin.
- Respin head: leg mutation-proved able to fail (4 cycles, 2 blind instruments agreeing), and its
  WINDOWS green was still luck — the MSG cells' identity ambiguity (two perches, one pid) was
  IDENTICAL on both platforms and only read_dir enumeration ORDER differed (NTFS: alice first =
  correct-by-luck pass; ext4: bob first = red). Every Windows pass of those cells — gate green at
  bf56baaa included — was void as evidence.

**How to apply:** after mutation-proving a cell, ask separately: is this green FORCED — could an
incidental mechanism (enumeration order, timing, a race won, a default, pool history) produce it
with the subject broken? A platform/box split where the ambient state is IDENTICAL is the tell that
the split rides an incidental mechanism, not the code. Fix = remove the incidental mechanism from
the loop (there: rig binds distinct pids so the tie never exists), not just the failing side.

See [[a-battery-is-silent-about-arms-no-cell-drives]] (the first half's entry),
[[identical-readings-across-opposite-outcomes-indict-the-meter]] (sibling meter rule).
Origin: releases#234 respin RCA, run 33231934813, todlando's 4-point instrument + Windows control;
leg (c) detect_self_by_ancestry tiebreak-by-enumeration-order, fix shapes ruled 2026-08-29.