The multichannel approach of XPS and XAS is now well documented. The polarisation-dependent Cu K-edge spectra of the square planar cuprates account for an anisotropic weighting of the two well screened and poorly screened channels. The R-2 dependence of the energy position of the 4p antibonding transitions is viewed specifically for a host wide band of p symmetry, for which the dispersion is approximately parabolic.