docs: correct two stale gotchas, and record the N-1-guarded-edits shape

repo-map gotcha 24 named TransposeAxes and CycleAxis as the only effects
calling reset_cursor, and listed nine others as renumbering the grid without
resetting. improvise-9mo9 closed that the day before: all of them reset,
thirteen in total, SetPageSelection conditionally. The paragraph named as
absent the exact set that was by then present, so it read as a survey of
outstanding work. Re-derived by brace-matching impl Effect blocks, and the
derivation is published beside the list so the next reader can re-run it
rather than trust it.

gotcha 44's group_of sentence said "nearest preceding header ... changing
that means changing AxisEntry and is filed, not smuggled in". improvise-gd83
landed that change in PR #77: AxisEntry::GroupEnd exists and group_of answers
membership. Names the two that are still open beside it, h0iv and 1wl0.

Three doctrines added. The one worth the space is
name_the_test_that_fails_when_only_this_edit_is_reverted: three independent
reviews in one wave found the same shape, a repair of N edits where N-1 are
guarded and the last carries a careful comment instead of a test — and the
unguarded edit is reliably the one the author understood best.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FC2jVn8Au7E9JPkw6bwXXH

prolog-sessions/kb.pl

@@ -231,6 +231,10 @@ doctrine(an_observation_correct_about_what_changed_can_be_wrong_about_when_it_is
 doctrine(a_siblings_unmerged_pr_is_invisible_to_bd_search,'AGENTS.md requires a bd search before filing. In a parallel wave that is not sufficient: a fix living in a sibling agent UNMERGED PR is in no tracker state at all, so the search correctly returns nothing and the duplicate is filed anyway. Observed 2026-09-20 -- the tooling agent filed improvise-v5pc to restore a deleted help assertion while the harness agent was landing exactly that in PR #72. Neither agent erred. Check OPEN PRS as well as the tracker, and have the orchestrator reconcile filings against merged work at wave end rather than trusting each agent to have seen the others.').
 doctrine(a_hard_reset_discards_knowledge_written_to_the_working_branch,'The orchestrator wrote doctrines to kb.pl on local main, pushed each as a branch, then ran git reset --hard gh/main to resync -- twice -- and silently discarded six clauses that existed only in the unmerged local commits. Nothing failed: kb_consistent passed on the reduced file, the counts simply read lower, and the loss was found only by grepping for clause names remembered from the session. Two rules follow. Write a fact ONCE, on the branch that will carry it to main, not on a local main that is going to be resynced. And after any reset or force-move of a branch holding knowledge, re-count the predicates and diff clause NAMES against what you believe you wrote -- a total that merely looks plausible is the same non-evidence a passing test count is.').
 doctrine(a_checker_that_reads_headings_cannot_see_a_contradicting_body,'check-evidence validates that a heading names a test that exists. It says nothing about the PROSE under the heading, which is what a human actually reads. Demonstrated on this repo 2026-09-20: renaming a retired entry to the test that had been restored made the checker green while the body three paragraphs down still said \"The test no longer exists\" and \"nothing replaced the assertion\" -- one entry making mutually exclusive claims, and the gate could not see it because the gate was never about that. Found by review, not by the checker. The general form is that a mechanical check licenses exactly the claim it makes and no neighbouring one, so a rename is a read of the whole entry rather than an edit of its first line -- a_fact_stated_twice_is_changed_by_grep applied WITHIN a document rather than across them.').
+doctrine(a_cost_note_names_the_half_the_author_was_thinking_about,'Twice now a reviewer has been asked to check a claim of the form \"X is now O(n) where it was O(1)\", and both times the interesting answer was not whether the claim was true but WHICH SIDE OF IT A READER WOULD ACT ON. On PR #76 the author wrote that the cost is \"O(cells) per CellData OR LayoutGeometry effect, where it was per LayoutGeometry effect\" -- which reads as though CellData is the newly burdened path. Measured at 18,000 cells it is the reverse: CellData was ALREADY O(cells) through record_fingerprints, so widening it is a constant factor (+27%), while LayoutGeometry went from O(config) to O(cells + config) and got 33x slower, 78us to 2.63ms, on the held-key-repeat operations. Not dishonest -- the author was thinking about WHICH EFFECTS NEWLY QUALIFY rather than WHICH PATH NEWLY CHANGED COMPLEXITY CLASS, and those are different questions with different answers. A cost note is worth a measurement precisely when the author can say confidently which half is worse, because that confidence is what stops anyone measuring.').
+doctrine(name_the_test_that_fails_when_only_this_edit_is_reverted,'A repair is usually N edits, and the failure mode is that N-1 are guarded while the last is explained in a COMMENT instead. Three independent reviews in one wave found the same shape: improvise-mai9 (the helper was tested, the caller that actually rendered was not), improvise-0x9u (preventDefault and the close/dismiss split were both tested, the drawn-vs-seed restore was not, and reverting it shows 18400 where 18,400 belongs on the shipped demo), improvise-o31u (the phone arm was measured, the desktop arm was justified by a mechanism measurement contradicts). The unguarded edit is reliably the one the author understood BEST -- which is why it carries the most careful comment, and why it felt covered: the comment is doing the work the test should, and it reads as evidence because it is the most thoughtful thing on the screen. The check is per-edit, not per-fix: for each distinct edit, name the test that fails when ONLY that edit is reverted. A line with a comment and no answer is the line to inject.').
+doctrine(a_stale_list_of_what_is_missing_is_worse_than_no_list,'repo-map gotcha 24 named TransposeAxes and CycleAxis as the only effects calling reset_cursor, and named SetAxis, HideItem, ShowItem, ToggleGroup, TogglePruneEmpty, AddCategory, RemoveCategory, AddItem and RemoveItem as renumbering the grid WITHOUT resetting. improvise-9mo9 had closed that the day before: all of them reset, thirteen in total. So the paragraph named as ABSENT the exact set that was by then PRESENT, and read as a survey of outstanding work rather than as history -- strictly worse than saying nothing, because it invites an agent to re-fix what is fixed. A list of what is missing decays in the one direction that looks like a to-do. Where the set is derivable, publish the DERIVATION beside it: awk over impl Effect blocks for reset_cursor, brace-matched rather than grepped.').
+doctrine(two_counts_from_two_derivations_are_not_one_fact,'Thirteen effects call reset_cursor and thirteen declare Model(LayoutGeometry). The counts are equal and the SETS ARE NOT: CreateView, DeleteView and SetNumberFormat declare the kind and never reset; SetPageSelection resets only conditionally. Equal length invites reconciling one list to the other, which silently changes what one of them means. Same shape as the wasm bundle being seven crates while its CI gate covers eight -- neither number is the other one typo.').
 work_done('improvise-8tk',bug_fix,'ZZ/:wq quit even when the save failed, silently discarding the model. Save now aborts the effect batch on failure; save_to_current_path/1 returns Result<String,String>; three tests in ui/effect.rs.').
 work_done('improvise-907',bug_fix,'Import wizard step machine redesign: validation_error() gate at ReviewProposals (no-category and over-limit), history-stack previous() bound to Left on every step, and Done made a real confirmation step holding the built workbook. Superseded improvise-gfq, improvise-o1c, improvise-c6j.').
 work_done('improvise-6sq',wont_do,'Merging EditOrDrill and EnterEditAtCursorCmd into one EnterEdit{mode} is not safe: they differ in WHEN the cell value is read, not in a mode parameter. Added ui/app.rs::tests::i_and_o_diverge_on_an_empty_records_grid as executable evidence.').