Analysis of Landauer's comment on ``Exact linear-response result for the driving force in electromigration''
It is elucidated that the degree of consensus concerning electromigration theory, referred to by Landauer, was founded on weak grounds. Further, his counter example to the new exact result is shown to be not valid. Finally, it is made clear that a conclusive result for the driving force can be derived only from a theory of electromigration which describes the local situation at an impurity exactly. In this respect a momentum-balance consideration, describing a bulk situation and leading to a force per impurity, necessarily fails.