The width and the null

Paper H of the Fenocosm arm of the Feno program — the program's methods-core deposit. Abstract. The standard test for multifractality in a time series compares the width of an MFDFA singularity spectrum against an IAAFT surrogate ensemble, and a null result is routinely read as evidence that the series is linear. We measure that test's power on its own canonical positive control and find it near zero: on a deterministic binomial multiplicative cascade the MFDFA width flags 1 of 24 realisations — statistically indistinguishable from the rank test's own false-positive floor of 2/51 ≈ 0.0392 — where a wavelet-scattering omnibus at matched specificity flags all 24. The mechanism is measured rather than asserted: on the binomial the IAAFT null hands back 0.939 of the original's own width, against about half on every stochastic cell with a non-trivial width, because the binomial's multifractality is maximally marginal-encoded and IAAFT returns the marginal exactly. A pre-registered σ-axis battery then falsifies the paper's own broader hypothesis: the blindness is not generic to multiplicative cascades but specific to the deterministic multiplier — the width's detection rate climbs 0.042 / 0.375 / 0.750 / 0.875 across σ = 0.30 / 0.50 / 0.70 / 1.10 while the omnibus holds 0.958–1.000, and at the binomial's own σ-equivalent the stochastic twin is flagged 18/24 where the deterministic original is flagged 1/24. The paper absorbs the falsification as the stronger argument: the converse inference "null ⇒ linear" dies not because power is uniformly zero but because it is truth-dependent by a factor of twenty in a direction no analyst can observe. A reporting standard is proposed, and the omnibus's own high side (isolated singularities; from-scratch specificity) is priced rather than hidden. Priority and scoop context (why this record is deposited). This is the Feno program's #2 publishing priority and the one carrying its largest scoop risk. It engages three named, currently active external lines — the t_MF robustness paper and its 2026 sequel, a multifractality-toolkit preprint, and a high-side audit programme revised in August 2026 — and it does so by telling a live literature that its standard test is uninformative in a specific, measured way. It had no DOI and no priority date before this deposit. Zenodo requires no endorsement; an arXiv posting (physics.data-an / astro-ph.IM) follows separately. The paper offers adversarial collaboration to the authors of the counterclaim it engages, and it states its own single-author, no-domain-collaborator position as a limitation rather than leaving a reader to infer it. Corrections carried in this version (2026-08-30). Two, both against the paper's own standard. The rank-test false-positive budget is 2/51 ≈ 0.0392, not the 1/51 ≈ 0.0196 an earlier correction paragraph stated (ranks 1 and 2 of 51 both clear p < 0.05), and the dependent binomial for 1 flag in 8 seeds is ≈ 0.274, not 0.147; the citation gate had hard-coded the erroneous value and now binds the correct one. And the IAAFT fairness certificate is restated per cell — spectral residual ≤ 0.037 on the pre-registered σ grid, 0.085 on the σ-equivalent anchor, 0.351 on the deterministic reference — with the note that the anchor's residual biases its own 18/24 upward, and the σ = 1.10 grid cell (21/24, residual 0.037) named as the clean corroboration. Deposit note. All seven Feno-program repositories are private and remain private, so this deposit is standalone: it carries its own reproduction materials, its metadata contains no repository link, and sibling work is referenced by DOI rather than by repository path. Related Zenodo DOIs cited below are reserved with publication pending. Part of the Feno program. The source repository is private; the reproduction materials for this record are contained in the record itself. Version 2 (2026-09-01): reference-list publication-status notes corrected (the program's reserved DOIs were published 2026-08-31); content otherwise unchanged. Version 3 (2026-09-15). Adds a dated Addendum (2026-09-15) carrying the irreversible-but-linear null (Fenopan record v20, 10.5281/zenodo.22759725), the attribution battery (record v37) and the t_MF robustness battery with its rescope (record v38), and the measured surrogate-band convention (record v57). No sealed number of the original paper changes; the addendum reads the records and edits nothing in place.