Comment on “Indirect CP violation in the B-system”

In a recent paper, Bañuls and Bernabéu have claimed the existence of a new form of indirect CP violation which would have its most prominent manifestation in the Bd-B̄d system. I analyse this claim in detail. I emphasize the fact that it is necessary to take into account the precise experimental method if one is to identify correctly the weak phase that one is about to measure.