But she was invariably calm and professional on the witness stand, earning praise from the prosecutors whose cases she was supporting. As Bentley repeatedly testified before grand juries, congressional committees and jury trials, however, she refined and embellished some details of her story. Information passed to her about a process for manufacturing synthetic rubber that was originally "vague" and "probably of no value" became "super-secret" and "an extremely complicated thing." She would also assert that her espionage gave her advance notice of the Doolittle raid on Japan and the D-Day invasions of France, both claims that appeared to have been exaggerated.