I am having an issue with a branching model when the iteration tool is used. The test code/scripts/models are in Google docs or arcgis forums
It runs and creates both versions of the process whereas it should only have either _GradedNULL or GradedDown. The test is simple and works.
The reason to do this is that the grading down set of processes takes a few hours to complete on each of the input text file and each area has more than 70. So if this branching worked it would save days of processing time.