The keyboard shortcut does show up when you run the ListCommands under Word Commands with the command name Distribute Para. It is possible to load it as a QAT or Ribbon modification in Ribbon versions.

Of course the last statement in the tooltip is silly, or someone has a very distorted idea of "clean look."

Although it shows up in ListCommands in Word 2003 and the keyboard shortcut works, it does not seem to show up under All Commands for customization of toolbars or menus. (If support for East Asian Languages is turned on it does show up on the Formatting toolbar without customization.)