While some people believe they can be flexible and want nothing more than a statement that says each will have free and generous access to the children, at some point, there can be a wrinkle where the parents are not in agreement.
If disagreement happens, and there is a good chance at least one will, how will you make a decision?
If you need a Judge to make the decision, what happens while you are awaiting trial?
Where are the children? When do you get to see them?