Feathering Notes:
If you have multiple objects selected, the feather appears around each object. If you group the objects, the feather appears around the outside of the group.
Objects with bevels or contours:
Selecting only the object adds the feather to the outside of the object, not to the bevel/contour.
Selecting only the bevel/contour adds the feather to both the inside and outside of the bevel/contour.
Selecting the object and bevel/contour adds the feather to the outside of the object and the inside and outside of the bevel/contour.
If you want to feather only the outside of the bevel/contour, group the object and bevel/contour before adding the feather.