Your right Brian...follow instructions, a lot less room for error if you do.
PPG does recommend DBC 500 as a clear blender, it is a transparent base coat and uses the same DT reducers as regular base coat...(see the link mitmaks, same reducer...so it's compatible). By using this product you are filling in sand scratches on your blend panel and eliminating metallic's to fall into them, giving you sand scratch lines when you clear coat. DBC 500 is also used as a mid coat carrier for pearl top base coats and specialty colors in PPG's Vibrance line.
As Brian said, follow the Tech sheets.