yesh, Big D nailed it in one.

How else do you think the Remnants came to be in AC?

In Cloud's final battle with Sephiroth he shattered the 'will' of Sephiroth's spirit, which was controlling Jenova's body. Sephiroth's spirit, you see, never merged into the Lifestream because he resisted it via power of will.

When Cloud shattered that spirit, the remains became the Remnants. Again, the Remnants were just parts of Sephiroth's spirit in Mako colacecsed into material form, all pulled together by the power of will.

yarly!