whys every1 going crazy over that 1 line that Tobi said. Tobi and Kakshi had encountered each other several times and have talked before, so Tobi obviously knows about Kakashi. The last time Obito talked to Kakashi was when Kakashi was focused on getting the mission done, and Obito had changed him, so i doubt Obito had known him that well. And if Tobi had known Kakashi before this, i still doubt its Obito because Kakashi personality is totally different than when he was in Minato's squad. And also, if they had known each other, the answer is probably in the previous chapter, im predicting that Orochimaru's scroll is some type of time travelling jutsu, and Tobi is Sasuke.