I believe Eliezer's discussed this issue before. If I remember correctly, he suggested that a CEV-built FAI might rearrange things slightly and then disappear rather than automatically solving all of our problems for us. Of course, we might be able to create an FAI that doesn't do that by following a different building plan, but I don't think that says anything about CEV. I'll try to find that link...

Edit: I may be looking for a comment, not a top-level post. Here's some related material, in case I can't find what I'm looking for.