> > Some debate for sport/fun

> In the context of a serious discussion, I believe the term for this is "trolling".

That's not always true. Have you never had a sporting debate with a friend who's opinion you knew full well going in?

In addition, a common debate preparation tactic for "serious" debates is often to argue from the opponent's side. This forces one to better understand the opposition's stance, better prepare for common responses and assertions, and discover potential logic flaws in one's own position.