Review of #9 found the methodology section falsified by that PR and owned by
nobody — the scoping that fenced it off was wrong, #8 never touches these
paragraphs.
Three fixes:
* The PATH-stub paragraph named 8a and 8b as the seed suite's stubs. It is now
four scenarios on two commands: 8a/8b/8c stub `cp` at the clone, 10 stubs it
one level down at the per-file unshare, and 8d stubs `stat` — a mechanism
the paragraph did not mention at all, and the only way to make an identity
that could not be READ the sole witness.
* The assert-which-guard-fired paragraph cited issue #5 as a live example of a
surviving mutation. #5 is the issue this PR closes, so a reader following
that citation landed on "removing it leaves every suite green", which is no
longer true. Scenario 9's own sentence stands — the matrix confirms it
survives every mutant — so it now says WHY it survives (an unreadable source
leaves the staging dir at mode 000, and the unshare pass aborts the clone
before the copy's exit status is consulted) instead of citing a closed
issue.
* Added the mutual-masking hazard the sweep turned up, since it is the general
lesson rather than a fact about two particular terms: two guards that can
each catch the same fault make each other unnecessary, so no fixture built
around that fault pins either one.
Also names scenario 8d for what it is in its own comment — a regression guard
on a defensive term, not a reproduction of a reachable state. Every route to
the state it constructs is closed off (a rotation hands the witness to 8a, a
genuinely absent source hands it to 8c), which is the reason it is worth
pinning rather than a reason to doubt it.
claude
eb7878b822
