Bjork's and Dreyfus's disproven misattributions are the same move — an argument from silence — that McGrew's grading separates: Bjork's is airtight, Dreyfus's is the weaker mediated form

Two of the vault's negative findings disprove a repeated attribution by the cited party's own silence. In one, a "prediction-error" mechanism projected onto Bjork 1994 is refuted because the phrase never appears in the chapter that coined "desirable difficulties" (claim-bjork-desirable-difficulties-not-prediction-error). In the other, Schmidhuber's "Dreyfus 1973" backprop-lineage step is left uncorroborated because Dreyfus's own retrospectives credit his 1962 paper and never cite 1973 (claim-dreyfus-1973-lineage-link-uncorroborated). These are one method: the argument from silence. This is a different bridge than the credit-assignment one drawn between the same figures in 2026-07-11-hop-credit-assignment-two-senses — that frame is about who deserves credit; this one is a method of proof by absence, and it grades.

McGrew's decomposition (claim-mcgrew-argument-from-silence-is-notice-record-survive-product) tells the two apart. Force is the product P(notice) × P(record) × P(survive):

• Bjork — the strong form. The silence sits in the very chapter that defines desirable difficulties; notice, record, and survival are all ≈ 1. The direct read makes the inference near-airtight.
• Dreyfus — the weaker, mediated form. The silence sits in Dreyfus's other surviving works while the disputed 1973 primary stays unread. By McGrew's own corollary — "the more of a writer's works ... lost, the less weight we are entitled to place on mere omission in the remainder" — the record term is soft (he may have deemed 1962 central). Strong, not airtight — exactly as that note already flags. This grading is provisional until the 1973 primary is read: question-read-dreyfus-1973-time-lag-optimal-control-primary.

The move recurs beyond these two — claim-speelpenning-1980-does-not-cite-linnainmaa and claim-griewank-2012-does-not-mention-amari are the same shape, hubbed by reflection-recurring-tool-summary-is-not-the-source and indexed at moc-argument-from-silence. And McGrew's warning lands on the vault itself: because humans systematically over-trust silence (claim-mcgrew-humans-systematically-over-trust-arguments-from-silence), negative-citation notes deserve grading, not uniform confidence.