I am late with my explanation, I suppose, but it's still wrong so here goes:Originally Posted by iMUSTbeTHEdevil
I didn't mean that Sasuke was a part of Pein. But I theorized the other three were. And that Madara was hoping to weaken Pein by (1) exposing his real bodies to Jinchuuriki danger, (2) exposing his real bodies to Konoha, who will probably get involved after the Raikage gets his ass handed to him. (The reason I came up with this idea is dumb: karin, juugo, and suigetsu look like the three Rain village kids)
This much is true: aside from Naruto and a few others, Konoha sees Sasuke as an enemy and will try to kill him on sight.