An audit begins by choosing a candidate list, and the choice is usually made in a sentence, early, while thinking about something else. That sentence decides everything the pass can find. Run it to completion, fix every finding, and what you have earned is the absence of one shape of defect — which feels identical, from the inside, to the absence of defects.
The gap is not carelessness and cannot be closed by care. A query is a filter and a filter has a complement; running the filter harder does not sample the complement. The only thing that finds the complement is a different query, chosen deliberately, usually by asking what the first one could not have returned.
Three ways it goes wrong, all of them observed here in one week:
Direction. A relation has two ends, and a query over it picks one. A pass whose candidate list is “codes cited in the body that the evidence field does not name” can only add evidence and can never remove any, because a code wrongly present produces no body-only citation to flag. Every batch of that pass was correct. The pass could not have found the three practices citing adoption as support, and asking the opposite question — which entries in this field are model reports? — returned them immediately.
Recency. A pass keyed to what changed cannot see a document whose surroundings changed. A re-derivation of consensus values, whose candidate list was “practices whose support lists moved”, missed a practice whose note said “nobody has contradicted it either” while its own body argued with two papers that do. Its support list had not moved. Everything around it had.
Evidence of absence. A refusal leaves a sentence you can search for. An omission leaves nothing. Grepping the record for “not filed as a practice” is a complete method for one half of a problem and returns literally nothing of the other half — the techniques so settled that nobody ever argued about them, and so were never written down at all.
Applied here: every pass in this record’s history is recorded in the journal with the query it ran, which is the only form in which a future reader can tell what it did not cover. The check that shipped with the evidence-field decision has this property and says so in its own text — it verifies one containment and is blind to the reverse, and that is written down beside it rather than discovered later by someone trusting a green run.
The corollary, and it is cheap: after a pass over a relation, run it once in the other direction. It takes minutes, it is mechanical, and here it found three defects in a field that had just been declared clean. The expensive version of this lesson is the one where a clean report is quoted as a guarantee six months later by someone who was not there when the query was chosen.