Sources: 2026-08 / week-2
Claim ledger for "Your Best Leader Did Not Get Worse."
| Claim (as written) | Source | Link | Status |
|---|---|---|---|
| "A study of the sales forces of 131 firms found that strong individual performance raised the likelihood of promotion and then predicted a decline" in the results of the teams the promoted person led. | Benson, Li & Shue, "Promotions and the Peter Principle," Quarterly Journal of Economics 134(4), 2019, 2085-2134 | https://academic.oup.com/qje/article/134/4/2085/5550760 | verified |
| Novel, ambiguous problems draw on the capacity to reason in real time, tied to working memory and distinct from stored knowledge (fluid vs crystallized ability). | Cattell-Horn fluid/crystallized framework; working-memory-to-fluid link per this study | https://www.sciencedirect.com/science/article/pii/S0749596X25000415 | verified |
| The adult brain restructures under sustained demand; London taxi drivers showed larger posterior hippocampi than controls, increasing with experience, and change appeared within individuals as trainees qualified. | Maguire et al., "Navigation-related structural change in the hippocampi of taxi drivers," PNAS 97(8), 2000; longitudinal follow-up Woollett & Maguire 2011 | https://www.pnas.org/doi/10.1073/pnas.070039597 | verified |
| The adult human brain continues to generate new neurons well into later life. | Boldrini et al., "Human Hippocampal Neurogenesis Persists throughout Aging," Cell Stem Cell 22(4), 2018, 589-599 | https://pubmed.ncbi.nlm.nih.gov/29625071/ | verified |
| Container / contents distinction; capacity as a developable baseline; Neurometric reveals capacity and where it is constrained, distinguishing a developable gap and where development converts. | Vanaya NeuroTech, Partner Certification Module 01, Neurometric Essentials v1.0, sections 2.1-2.2 | Internal document | internal |
Handling notes
- Neurogenesis is contested. In the same year as Boldrini, Sorrells et al. (2018, Nature) reported that hippocampal neurogenesis is undetectable in adult humans. The field remains divided. Per Twin, Vanaya backs neurogenesis as a firm belief grounded in Dr. Lyra's paradigm, and the article cites the supporting primary literature (Boldrini) rather than asserting it bare. The developability argument does not depend on neurogenesis alone: neuroplasticity (Maguire) carries it independently and is not contested. If Dr. Lyra prefers, neurogenesis can be cut with no damage to the section. Flagged in frontmatter.
- Fluid-capacity mechanism. The Cattell-Horn fluid/crystallized distinction is well established. Mapping it onto the module's "capacity vs memory" model is our framing; Twin approved proceeding, Dr. Lyra to confirm the mapping. Flagged in frontmatter.
- Growth-potential framing (section "You are deciding on the variable you cannot see"). Stated as reading current capacity and where it is constrained, which is defensible from the module (capacity is a developable baseline; Neurometric identifies brain gaps and potentials). Deliberately not stated as a predictive "growth score," which the module does not claim.
Reused from week 1
- The container / contents distinction and "capacity is a baseline, not a verdict" were established in week 1 and are carried here, not re-argued. Week 1 owns "the record does not predict performance in a new organization" (Van Iddekinge); week 2 deliberately does not repeat it, using the Peter Principle (promotion criteria and managerial decline) as a distinct claim.
Not used
- Executive failure-rate statistics remain cut (see week-1 sources): the 30-to-75 percent spread across sources is not a finding.
- Beilock & Carr (choking under pressure) was held in reserve for week 2 but not used. The stall here is a capacity-ceiling and novelty story, not a pressure-induced-decrement story, and Beilock's counter-intuitive direction (high working memory individuals choke) would complicate rather than support it. Still available for a future pressure-specific piece, scoped to working memory.