Who won't know this situation? You open up a file in /etc using nautilus, it opens the file with gedit, you make your changes, click save and "ohhhw, I forgot to open it as root". So you open a terminal(or alt+f2), sudo gedit /path/to/file and make the changes again.

I think it would be much easier if gedit would just say "Hey, you are not root. Would you like me to save it as root?" and asks for the password.

I also have an idea how to implement that in the GUI. If you opened up the file in gedit without root rights and click save, a dialog popup thingy like this: http://yafu.wh-forum.de/251962541/Bildschirmfoto.png(I took a random binary file to show the form of that dialog) could open, telling you that you have to be root, and if you click on a button inside this dialog it would ask for the password(or take it from the keyring or something like that), and save the file as root.
Maybe it could even be implemented in GVFS itself, so every application could benefit from it.

How do you think about it?

Thanks, 
Lisa Denia