This plugin is designed to aid in layout/formatting. It allows you to copy and paste something which, before now, was not possible to copy and paste.
You can copy and paste music including signatures and text, but you could never keep the formatting intact, which is a rather important part of your score.
With this plugin you can make a selection from which you would like to copy the layout and then type in the bar number you would like to paste this layout too.
If you ever deal with book layout or find yourself making a lot of manual formatting marks, your life will probably become a lot easier with this plugin.