Actuation Force Tensor and DOF_MODE_NONE

I have the “driveMode” of all my actors’ DOF properties set to DOF_MODE_NONE. When I apply nonzero torques to the DOFs with set_dof_actuation_force_tensor(), the DOFs move. Is this expected? I assumed that a torque would have no effect on a DOF with drive mode DOF_MODE_NONE. I am using Preview 2.