I think that it is highly significant that the text critiques Michael's lack of judgment.  His own paralysis at Hanna's trial, a moment in which he could have spoken for her and taken action is reflective of Germany's own inaction and passivity in the face of Hitler and the Nazis.  The fact that the text does bring questions to this condition is what enables it to pivot from a literary narrative to a work that raises significant historical questions.  The entire focus of what is transpiring is to determine "why" what happened happened.  In the same light, the reader must ask the same questions of Michael and his own paralysis with and concerning Hanna.  In asking this question, the text is able to bring questions to both the text and the historical time period that envelops the text.  I think that it is to this level that the text is significant in raising questions of Michael, his lack of action and his overall lack of reliability as a narrator. In being able to construct a world filled with questions, there can be a more worthwhile discourse and dialogue that will enable a better sense of "why" things have happened and continue to happen to emerge.  For this reason, it is significant that the text makes a case against Michael.