Board Thread:Theories and Speculation/@comment-28939725-20161201164545/@comment-734582-20161205113209

Actionmanrandell wrote: When kakashi used susanoo it clearly was not Obito's chakra. it was clearly Kakashi's thats why his susanoo had a scar across its right eye, just like kakashi. Left eye. Besides, Kakashi was the one manifesting it, so it makes sense it looks like him.

EDIT: Chapter 567 also puts forth both theories: Obito either can't use the Paths because he uses all his concentration to keep the Biju in check (since he's not just controlling the 6 paths, he fights alongside them AND keeps 6 biju in check) or he won't waste chakra on these techniques since the counters are known. Or both.