While looking for a display option in my assembly FeatureManager tree one day, I discovered that you can actually show the custom property for Description in the FeatureManager tree. You can show the name of the file, the configuration name being displayed and of course the display state of this file as well. So to turn on this option for showing the file's description, you just need to first access the Tree Display options by right mouse clicking on the top level of your assembly FeatureManager Tree.
Then choose to select the Component Description option. Then make sure you actually have a value typed into this field for a description as a custom property and it will show up in this assembly's FeatureManager tree.
And there you have a quick way to show the Description Custom Property from any SOLIDWORKS model referenced inside your assembly files.