Board Thread:Versus Debates/@comment-27916438-20160628002237/@comment-5407586-20160703130043

Obito said that Sasuke couldn't see through Itachi's lies. That much isn't debatable. Sasuke could break out of Tsukuyomi with a regular Sharingan, but one might say that Itachi didn't go all out in their fight. With the Eternal Mangekyō, which grants him Itachi's ocular power on top of his own, there's no way Sasuke can't see through Itachi's strongest genjutsu. So yes, genjutsu is useless in this fight.