Paying attention to using the correct object styles when creating Revit families is important. In BIM protocols there are usually very specific settings assigned to object styles that need to be adhered to as much as possible. When these protocols have deviated from an extra complexity results that need to be managed, and so this should rather be avoided.
Each time an extra subcategory is introduced, this is also inserted into a project on the loading of the family. When importing a CAD drawing and exploding it in a family, the layers on which the objects are get mapped or created as subcategories. All the objects introduced this way need to be assigned to the correct category or sub-category and the extraneous subcategories deleted before insertion into a project.
If you need training using Revit or help in your office to apply it correctly, please contact Micrographics so we may be of assistance.