Let you delete one finder instance from one of your screens, with this you may dedicate one screen to full screen apps only and the other for the rests. It’s pretty annoying to have finder selected in the secondary screen but since it is an “extension” of your primary desktop you see no icons, so, Finder can use both screens but it won’t change to the whole desktop when you select finder.

This is in first place inconsistent, and may be useless when you want to select some file from the desktop and the finder “part” that is visible is in the secondary screen. Putting the same desktop icons in both screens would definitively help, having only one desktop would be great!.