Hi,
That is ok, and I really do not want to see a fully structured tree. However, for end user convenience, it would be helpful if there would be a reply button at each reply visible - even if it would technically just be a reply to the main post.
The only difference that I would see between replys to the main post and replies to a reply would be the order in the view. Meaning that a reply to a reply should simply be located below the reply and not below the main post (above the reply it was replied to).
That would solve a lot of issues I think!
bye
Marcus.