James Reeves interviews professional armorer to discuss the shooting:
https://www.youtube.com/watch?v=XdwuXKeVe2Q
If the interview is accurate, there was a culture of negligence on that set.
At 2:20, the "expert" is already incorrect. Yes, the original camera crew had quit. Fact: the production company had already brought in a replacement camera crew. Halyna Hutchins was behind the camera because it was not even a rehearsal of the scene, it was a
blocking of the scene scene -- She was standing behind the camera in order to view the scene from the camera's eye, in order to decide how the scene should be blocked out (staged) for the best visual effect.
This is not insider information. This was made very clear in ALL the reports.
At 5:28 he says, "They're filming the scene." No, they weren't filming the scene. They were blocking the scene.
At 11:21 James Reeves says "She had intermingled live rounds with dummy rounds and handed that to Alex Baldwin." Wrong. Earlier in the video, the expert said that David Halls handed the gun to Baldwin, and EVERY report at the time said that. The expert did not correct Reeves.