It turns the outline itself into the interface between the user and program. Lawyers are familiar with outlines. Most should intuitively know what to do with the mouse or keyboard in a good outliner. Only a program dedicated to outlining is likely to provide this. Inspiration is such a program, and it takes only 9 megabytes of space.
Inspiration is so simple it can be used instantly.
Yet it is powerful enough to justify a 348-page manual that is loaded with tips and techniques. It is rare to see programs, particularly small programs, with substantive manuals that fat. This is the first manual in many years I compulsively read cover to cover. There is the basic Outline Mode, which performs a standard outline. The program also has a Diagram Mode, to which you can flip from Outline.