I'm working with CodePoint Polygons (areas for Postcodes) and have developed a Workspace to count addresses in each Postcode that are inside and outside a certain area. I'm using AreaOnAreaOverlayer to split the polygons into 2 where they cross the border of the other area. However, the consquence of this is that Vertical Street* polygons get merged (I think the Tolerance parameter is doing this), which causes one of the Postcodes to be lost. This means I don't get an address count for it.
I've tried using Group By Postcode, but this crashes the process because there are too many unique Postcode values. A WorkspaceRunner to process each Postcode separately seems overkill. I can do it by Using Attributes From One Feature, creating a List of Postcodes, then using ListConcatenator etc to re-create the deleted polygons after AreaOnAreaOverlayer has merged them. But this seems a rather tortuous way of doing it.
Any suggestions?
* a Vertical Street is something like a tall office block where different floors have different Postcodes.