Board Thread:Theories and Speculation/@comment-31966672-20200409171208/@comment-4961229-20200424150856

Sasuke never states that super tiny details are why he can predict movements. He simply states that he can see what Naruto's going to do next and react accordingly. In some translations, he says his eye shows him an image of his next movement. "Super tiny details" being the reason for this image are your headcanon.

Rock Lee only states that he doesn't have the eye to perceive and see through the counterattack at head on at that speed and that Sasuke has the Sharingan plus his speed. Kakashi once said something like Obito's eye allowed him to complete his jutsu. When does anyone else "constantly" say the Sharingan is needed for Chidori?