I don't think this type of behaviour should be allowed in this site. He asked the question, received the answer, and hided everything that answers were bound to. So what about future visitors? How can they understand the answers without understanding the question?
Modifying the scope of a question or changing it so much that the provided (and maybe accepted) answer(s) no longer make sense is not allowed. The edit should be rolled back (click on the edited [date] link to see the rollback option).
The question poster is now suspended. He is most likely related to this issue and this issue.