Board Thread:Theories and Speculation/@comment-26358288-20150630121218/@comment-734582-20150701105404

As the itachi vs Sasuke fight mentioned, the Sharingan is still a tool, just like Mangekyou. Sasuke broke out of it using the natural genjutsu and insight powers of the Sharingan. Genjutsu prowess isn't the same as breaking out of genjutsu prowess.

So, even though Sasuke doesn't use terribly powerful Genjutsu, he can break out of terribly powerful Genjutsu.