Board Thread:Naruto Discussions/@comment-4682609-20140806081616/@comment-3568954-20140806113422

ItachiWasAHero wrote: Well put it this way, Obito's Chakra which awakened Sharingan and Mangekyo and was most likely fused with Hashirama's since he had it so long(which is why he can use perfect susanoo), is now part of Kakashi. It helped him awaken his own Sharingan, which is also Obito's Sharingan. It is most likely Obito meant that Kakashi will eventually go blind, or simply lose the sharingans once they go blind, and revert back to his old eyes.

exactly one can not simply gain the sharingan by taking an uchiha's chakra into there body if that was the case orochimaru would have gained it years before. its my theory that because kakashi had the sharingan in his body all these years his body has acclimated to the sharingan. because of this when Obito's chakra revived and entered his body it attached itself to his optic nerves causing kakashi to awaken the sharingan and likely the same chakra that an uchiha gains. not to mention all those years of having obito's eyes has likely caused kakashi's body to acclimate to the uchiha DNA