Board Thread:Theories and Speculation/@comment-25547449-20160805204709/@comment-4912646-20160806023430

OnlineLurker wrote: Maybe i'm wrong but kaguya didn't seem to gain conscious until the shinju was cut down. The shinju(Kaguya) was talking to madara, right?

The juubi is practically kaguya's own bijuu mode, so it'd grant similar benefits. But unlike a regular transformation, she apparently isn't able to turn back to normal at will. Both times we see her revert to her humanoid form, she first has to absorb a large amount of chakra from the Infinite Tsukuyomi's victims. It stands to reason that this may not have been the case back when she first merged with the Shinju, or else why would she bother transforming and giving up control in the first place?