It doesn't create a fully functional remote control. All you can do is push content to a connected browser window. If the browser crashes, you'll need a keyboard or another remote access tool.
This tool is just a quick and simple way to make use of your extra screens. You can use a bookmarklet to make a webpage instantly appear on a screen, or with a tool using the REST API, you can make the screenshots you make instantly appear on an external screen.
Usually there is a lot of fuss when something breaks (finding spare keyboard and mouse, connecting it to hidden pc).
If I get this right, this will create a 'remote control' for each such screen, right?