I personally don't think Satan has been allowed to KNOW alot about the prophecies about him. I have always believed that Satan and "his" angels were kept in spiritual darkness. If this is true, then they don't know what will happen to them.
For example, when Jesus was expellilng demons, they would frequently ask that they NOT be sent to the abyss. There is no indication that he EVER sent any of them to the abyss. I don't think they knew what to expect or what Jesus plan was. I don't think they understood His second coming, or any of the prophecys related to it.
But I don't think that you can call Satan "dumb". I personally think he is a genious. I agree completely with Ding. It makes absolutely no sense to me that Satan can be spiritualized. That also violates the rules of hermeneutics. Hermeneutics state that unless directly stated or directly obvious to any reader, everything must be taken literally.
JWs spiritualize Revelation to a HUGE extent. They think the ENTIRE book is symbolic. So even when it speaks of a specific event happening, they spiritualize it and say that it occured during a 1927 district convention.
Satan is a real person just as God is a real person. I can understand not believing in Satan if you DON'T believe in God. I won't argue that with anyone. But if you believe in God as a real person, you MUST believe in Satan.