I think Opeth not using Steven Wilson for Ghost Reveries was the best thing they could have done. It showed the band is much more creative without him than with him. Not that Blackwater Park, Deliverance, and Damnation turned out bad, but they sounded affected to me. They weren't truly Opeth albums. They were Opeth and Steven Wilson projects with the Opeth logo on them, especially Blackwater Park and Damnation.
I really really hope they don't use him ever again.