What has led to this situation where we have double discussions shown?

In my opinion, this looks like a design mistake. (Or maybe it is incomplete and I don't see the full vision) hm://z6MkrbYsRzKb1VABdvhsDSAk6JK8fAszKsyHhcaZigYeWCou, can we develop a methodology which allows us to avoid this sort of issue in the future?