Comment on 'Non-monotonic projection probabilities as a function of distinguishability'

A recent work (Bjork and Shabbir 2014 New J. Phys. 16 013006) claims that nonmonotonic structures found in the many-particle quantum-to-classical transition (Ra et al 2013 Proc. Natl Acad. Sci. USA 110 1227-31; Tichy et al 2011 Phys. Rev. A 83 062111) are not exclusive to the many-body domain, but they also appear for single-photon as well as for semi-classical systems. We show that these situations, however, do not incorporate any quantum-to-classical transition, which makes the claims unsustainable.