  In 1989, Eberhard proposed a v-causal model where quantum correlations
between entangled particles are established by communications moving at a
superluminal speed v_t > c in a preferred frame. In successive years, several
experiments established lower bounds for the possible tachyons velocities. In a
recent paper, Luigi Santamaria Amato et al. performed an interesting east-west
aligned tabletop experiment under the assumption that the preferred frame is
the Cosmic Microwave Background (CMB). In that paper, they criticize
long-distance experiments but here we show that most of their criticisms are
not applicable to long-distance tunnel experiments where the highest lower
bound was obtained.
