PW tested it both way.. the opening post appearing on each page or the continuous ongoing posts without repeating the first post.
If you use an app you will see its not repeated. You see it only when you browse via computer. The feedback was that many member open the thread and as the most recent page or post appears first .. the questions, the opening post gets over burdened by the replies.. So the opening post is repeated on each page top so that anyone who clicks the thread could respond accordingly no matter whatever page the discussion is on going.
Yes it can be annoying.. your suggestion will be sent to developer again.