Even movies which are very good can have scenes in them that don't work very well. This is true of Titanic. There are many reasons for this to be the case. Or the Director, (one who has final cut) feels the scene is perfect the way it is and I'm just a crazy person with too much time on my hands. I'm not so sure when a scene sticks out like such a sore thumb.
Which scene? It's the Rose and Jack deck scene. The one where they are first getting to know each other. He insults her and then she in turn for no reason grabs his drawings and the scene changes. What!? Where did that come from? I believe it's not set up as well as it could be. It's a simple solution. Here's the scene as it exists.
I feel that it's choppy near the end and could have worked better if it were done differently.