Visibility Function on Dynamic Blocks

The block authoring palettes that were first included with AutoCAD 2006 have some very useful dynamic features.  Among them is the visibility feature.  With this command, you can create a pull down menu in your properties dialog box that will control the visibility of components of a block.  The current visibility displayed can also be exported via an attribute block.  This is a useful tool for quickly entering in attribute data via a quick pull down menu.