We pray in the name of him who received not a fulness at first, but the Prototype who showed us how to gain salvation.  In His name we pray because it is the path that he took that we must follow to the father.  When we pray in His name, our aim is to follow the path to salvation that was followed by Abraham, Isaac and Jacob, and our prayers in His name should tend toward those goals.  When we ask or act contrary to those goals, we are not really praying or acting in His name.