Attributes for a configurable product don't show in the layered navigation on a category page unless at least one simple product associated with that configurable product is assigned to that category. It seems to me that associated simple products for a configurable product should inherit the configurable products categories as well. As of now I have to go through all the simple products manually and assign categories.
Is this normal behavior in Magento? Do you always have to manually assign categories for simple products under configurable products so their attributes show up in the layered navigation?