Summary of the minimum distance, the mechanical luminosity, and the intensities predicted with a sole distribution of shock models for the shock-only scenario. Panel (a): Minimum distance as a function of the pre-shock density. The dashed line represents a 0.5 dex limit (i.e., a factor of three difference between observed and modeled line intensities) to guide the eye. Panel (b): Mechanical luminosity as a function of the pre-shock density. The green area represents < 1% of the estimated jet kinetic luminosity of 3C 326 N (see Sect. 4.3). Panel (c): Comparison between the observed line intensities and those obtained for the model at n_H = 10 cm⁻³, b = 0.1, G₀ = 10. Observations are presented as blue stars (see Table B.2) and modeled intensities are shown as open black circles.