Recently I was doing some research about scripting in League of Legends, and some advanced techniques that look like cheating. I came across this video: https://www.youtube.com/watch?v=hBwrGdUxr90
This technique is not useful, but I've wanted to try it non the less. What are you supposed to do is to bind move command to Z, attack move to X and Target champions only to Space bar.
As it turns out if you hold target champions only button (default `) attack+move (default Shift+right click) wont work or vice versa. It wont work if you bind it as in video, which is the same conclusion the author got.
The only function of this command is to ignore minions on move or attack (default Right click).
In my opinion this option (target champions only) should be fixed to include attack move, as well as attack or spell cast commands.