No because that requires significant code change. That thing has been there for over three years now (pre-dating the system we use currently), and I believe stfrn wrote it originally. I don't believe anyone has touched that code since.
EDIT: If I recall the left pane was supposed to be a tree widget showing possible items that can be made while the right pane was supposed to be a multiline text box with rationale. I've seen a prototype screenshot of it before but it was over three years ago.