i meant more the adding of a keyword rather than the semantics of the name. if we are talking of semantics it would be:  `return_eigenitems` or `return_solution_components` or `return_graph_decomposition` or something along those lines.

regarding whether this is used for diffusion embedding only, i would think that the eigenvalues and vectors would be useful for other things. but i feel that spectral embedding means something explicit so turning into a private function would indeed be better.