Board Thread:Episode Discussions/@comment-1251315-20161215125344/@comment-1512913-20161217003106

Note: there is actually no proof that Naruto tanked Toneri's attack with no damage, rather there is no evidence he got hit in the first place, the way the scene plays out, he might have been able to dodge in time, which would make more sense. For Sasuke's sword, when it was introduced, Sasuke stated that it possesses special properties, but we have never been told what they are, so it's quite possible that Sasuke was given a superior sword to Orochimaru's.

For chakra cloak, it's quite possible that the increased durability is a conscious effort, not automatic. But for Sage Mode, that seems to be always there, independent of intent or effort. So I suppose Naruto just wasn't toughening his chakra cloak and Sasuke's sword is just naturally sharp enough to pierce through Senjutsu enhanced body.