Yeah think she meant to say that Sasuke is just corrupted and rotten to the very core that his chakra is just pure evil. And remember what hte Kyuubi said? That Madara's charka was more sinister then his own? Sasuke became evil due to Madara and Naruto simply has a beast of pure evil within him. That is all.
I wouldn't be surprised if Sasuke's EMS wouldn't work on Naruto because of what Itachi did. Hell maybe Itachi made Naruto immune to it somehow. That way it will be just old school jutsu throwing and beating each other to a snot without spamming the Mangekyou all the time.