Board Thread:Versus Debates/@comment-26998824-20150927013622/@comment-9782468-20151102132119

Sasuke's Genjutsu is far from mediocre, he's actually very good at it. He just isn't as good as the masters is all.

Kakashi was able to duel Obito in Genjutsu and tie. Obito is probably pretty proficient with it, what with being trained to be a near mirror image of Madara in life by Madara himself and keeping Yagura in Genjutsu for so long