Comment on `Underlining some limitations of the statistical formalism in   quantum mechanics' by Fratini and Hayrapetyan
  We point out that Fratini and Hayrapetyan ignored the randomness of mixing, a basic request to prepare a statistical ensemble rather than an ensemble in general. Their analysis is irrelevant for standard statistical ensembles, their conclusions about the limitations of standard theory become unjustified. 
Andr\'as Bodor and Lajos Di\'osi
quant-ph