User blog comment:EmpyreanSmoke/Supernatural Q&A/@comment-79.115.70.149-20150829154139/@comment-24834479-20150830063423

I think that it has different effects on different Angels, or different types of angels. Or maybe there was more grace taken out of castiel, leaving him with less powers.

The vessel's soul will still be in the body, but the Angel's soul will still have control.