Question
Why does FME automatically insert a GeometryFilter transformer into my new workspace?
Answer
Some destination formats only permit features of a specific geometry type to be written to a single Feature Type. For example, a Personal Geodatabase Feature Type (Esri Feature Class) can hold polygons, or polylines, but not both.
When you read from a source dataset that permits multiple geometry types in a feature class, but write to a destination dataset that is restricted to a single geometry type per class then FME automatically creates a destination Feature Type for each geometry type and inserts a GeometryFilter to divide up the features on the basis of geometry. This ensures that no destination Feature Type receives features that it is not permitted to write.