Is there any explanation of what the "Virtual dependency" schema property type does in the Synchronization Editor?

Is there any explanation of what the "Virtual dependency" schema property type does in the Synchronization Editor?  This property type is only available after launching the Synchronization Editor with the "-d" developer mode argument.

The description text states that it "Provides a virtual dependency to control execution"; but I'm hoping to get a better explanation of what it actually does, before considering using it in PROD.

Using version 8.1