Comment on "Dislocation Structure and Mobility in hcp ⁴He"

In their Letter, Borda, Cai, and de Koning report the results of ab initio simulations of dislocations responsible for the giant plasticity. The authors claim key insights into the recent interpretations of (i) the giant plasticity and (ii) the mass flow junction experiments. The purpose of this Comment is clarifying the role of dislocations in the mass flow in conjunction with explaining that the part (ii) of the claim is misleading.