Validate residualization under natural construct–artifact entanglement
Establish an independently validated real-data case in which residualization is evaluated when the construct and artifact are naturally entangled, and determine whether the adjustment improves or damages construct validity in that regime.
References
There is no independently validated case here of residualization improving construct validity on real data where construct and artifact are entangled. The intervention audit establishes attenuation of the measured format contrasts in a design where the channel is label-orthogonal by construction; the observational regime supports the slice-restricted scope of Section~\ref{sec:attrdef} and nothing wider; the entangled region is covered by the controlled sweep and the semi-synthetic probe of Section~\ref{sec:entangled}, and by nothing drawn from natural data.