Phenomenon of spectral switches as a new effect in singular optics with polychromatic light

It is shown that the recently discovered phenomenon of so-called spectral switches has a natural interpretation in the framework of singular optics with polychromatic light and that it should be regarded as being primarily a manifestation of diffraction-induced spectral changes rather than correlation-induced spectral changes as was suggested in the original papers the first one appearing in Opt. Commun. 162, 57 (1999)] reporting this effect.