Original sentence: Alvarez also investigated the timing of the gunshots and the shockwave that disturbed the camera, and the speed of the camera, pointing out a number of details that the FBI photo analysts either overlooked or got wrong.Alvarez's theory had, however, been further refined and corroborated by other researchers.He produced a paper intended as a tutorial, with informal advice for the physicist intent on arriving at the truth of the case.Prominent forensic investigator Josiah Thompson, in his 2021 book Last Second in Dallas, closely examined Alvarez's experiment and found it flawed, suggesting Alvarez may have been politically motivated to oppose any theory suggesting a conspiracy to kill Kennedy
Edited sentence: Alvarez's theory has, however, been further refined and corroborated by other researchers.He also investigated the timing of the gunshots and the shockwave that disturbed the camera, and the speed of the camera, pointing out a number of things that the FBI photo analysts either overlooked or got wrong.He produced a paper intended as a tutorial, with informal advice for the physicist intent on arriving at the truth.Prominent conspiracy theorists attempted to refute his experiment – see Last Second in Dallas by Josiah Thompson