Do measured shot-duration patterns across 150 popular films support a 30/60/30 three-act split, and what act timings does the empirical literature actually report?

Cutting (2016, CC BY 4.0) reports, for a 150-film set of English-language popular films (a 160-film corpus 1935-2010 culled of films over 2.5 h and with intermissions), shot-transition and luminance patterns he reads as better fitting Thompson's four-act scheme than Field's three-act scheme: about 98% of protagonists appear in the setup window and mean luminance is lowest near the three-quarter point. Act proportions (about a quarter each) are Thompson's parsing of 73 films, quoted, not re-derived. Curator qualifications: Any statement must name this paper and its 150-film set; do not merge with Cutting et al. 2012's 160-film sample (AUDIT1 row 17). Not evidence that four acts is the true structure of film (author concedes boundary parsing and sample limits). Per-study figure counts (148 of 150 in Study 1) differ; numbers are as reported, not reproduced. Text only; no film analysis reproduced. Limitations: English-language, mostly US box-office films; one author's modelling choices. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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