Furthermore your asserted So  is not an absence of interference but the sum of two interference patterns which are shifted  That statement is not true There are at that stage in addition of pieces of equipment to the experiment two groups of photon splits that have opposing polarizations and the members of no pair of photon splits or copies of wavefunctions or however you want to verbally describe them being oppositely polarized cannot productively superimpose Even if the discussion were to be carried on entirely in classical terms and there were no individual photons mentioned it would be impossible to draw the equivalent to a classical picture of simple doubleslit interference A diagram of ordinary interference shows two diffraction patterns that are slightly out of phase along the xaxis of the detection screen In this placement of the two light waves there is productive physical interaction between the two waves The result is one wave with maxima of different magnitudes Walborn et al designed their experiment to upset this productive interaction by giving the two waves of light to put it in classical terms opposing polarizations DParlevliet claims that Walborn et al are mistaken and that interference between these two waves of light actually occurs Furthermore he asserts that there is not one interferenceproduced wave but two It is unclear what light wave is interfering with what light wave in the case of the first wave nor is it clear what light wave is interfering with what light wave in the case of the second light wave Furthermore it is not stated how with all of these supposed interference waves being incident on the same area of a detection screen experimenters could observe them to establish the existence of the real physical interactions that their theory predicts It appears that from one light wave emerging from a light source two light waves are produced by the action of the doubleslit diaphragm that the two light waves are oppositely polarized by the two quarterwave plates by unspecified means each of those two light waves is divided and finally there are four light waves These four light waves interfere two by two producing two interference patterns which are shifted  which are incident and superimposed on the same detection screen and are therefore obscured by each other However it has not been exlained how these two sets of presumed interference could ever be empirically confirmed  We are forbidden from publishing independent research or assertions unsupported by research in peerreviewed journals or other accepted sources  Therefore I must insist on adequate evidence for your assertion quoted above