Today, with all our fancy user interfaces, toolbars, menus and contexts, using a shortcut key or combination of keys, is always faster than using the mouse to navigate to a specific area in the user interface and then use one, two or more clicks plus mouse movements to select a particular command. Think about how difficult it is to select a command in a sub menu.
This is even more important for applications that mainly live from text-based input like mind mapping software. You constantly move your hand from the keyboard to your mouse (http://www.mouse.org/) and back.
While all of these movements and clicks seem to becoming second nature to you, it's still a distraction. You can simply avoid this distraction by using more keyboard shortcuts instead. Looking for shortcuts for the most frequently-made editing commands, makes a program more productive and fun to use.
Mindjet makes software that helps people visualise and use information. Its product enables individuals and teams to work smarter, think creatively, and save time every day.