Problem: ClipToGraphicExtent property of IExporter does not clip to graphic extent
When using ArcObjects to write an export function, the IExporter.ClipToGraphicExtent property does not actually clip the output to graphic extent.
The ClipToGraphicsExtent property is simply a flag that is used by ArcMap to determine how the exporter should calculate the extent of the export.
Solution or Workaround
When using ArcObjects, control the extent that is exported by using the IExporter.PixelBounds property.