What's the point of a debate? Show/listen to others, argue, and change your mind if they prove you wrong. It's pointless to debate with deiststheists, not only because faith is impenetrable to logic, as user2808054 pointed out, but because while an atheist is ready to change his mind, a deist is not. Never.
Is faith or logic the proper approach to go to a debate? Which one will let you come out of it wiser, by making you changing your mind if necessary?
Edit: this has reminded me of http://scienceblogs.com/pharyngula/2010/12/30/why-i-dont-debate-creationists/