This is not crucial, since it's only used for visual representation, but since we have it, we might fix it at some point.

Here's a DAG from an ne4np4 run of SCREAMv1 compset. There are self-dependencies (SC exporter), incorrect dependencies (cldfrac dep on SC exporter). Overall, the DAG also needs to be cleaned up. It was impl-ed in the early days of atm proc and field classes, so some assumption have changed, and the code can prob be made cleaner.