Comments on "Simulation of large magnetic islands: A possible mechanism for a major tokamak disruption"

In this Comment it is established that the numerical results for the nonlinear evolution of the $m=2\mathrm{}$ tearing mode are affected by the density of the poloidal grid. A coarse grid gives results that are quantitatively and qualitatively incorrect. The important qualitative error is that with a coarse grid the growth of the width of the associated magnetic island is exponential rather than algebraic.