This is actually something one of my white friends told me. I'm happy you were enlighten to research so if the movie did that, then great. With that said it only accents that Slavery has been watered down in American History which is basically with Mr. Gregory was saying in his comments. Our History books do not tell the full truth and kids in school are being lied to and denied the true history of Slavery cause America didn't want to look back. America had 2 Holocaust with what happen to the Natives and Slavery. But both have been watered down in our history. What happen to the Natives was genocide and what happen to the Blacks was cruel. As for the disturbing images. Watch the beginning of "Amistad" on that ship, ish like that happen.
I've watched Amistad and Roots at school. I've watched a lot of films on the subject, and I honestly think QT pushed the limit in showing the cruelty and it made an impact on me personally.
The worst part about the film honestly was the hot box. No violence involved but just the concept of absolute torture, mentally and physically. It made me uncomfortable, and I don't get uncomfortable watching a lot of things, especially things I know not to be real footage.
I do think you're right about American education in general, ESPECIALLY towards the Natives. This is the same in Brazil as well. Like I said on an earlier thread though, I grew up learning a lot about African-American history in school, and I was introduced to Amistad and Roots through there, as well as the Autobiography of Malcolm X but I grew up in South Florida.