My whole idea about everything input lag related is that sometimes people are to focused on "the human eye". Sure an image is smooth at 25 fps but the gameplay isn't. It's called input lag. Even if they eyes can't see, you're moving around your mouse, you're sending feedback with another sense besides your eyes. As soon as these 2 (sight and touch) feel "out of sync" it's usually input lag. I'm liking the F1 pilot comparison. Just like the experienced F1 pilot, an experienced FPS player can spot differences in input lag very fast. I even notice the difference between 120 Hz and 60 Hz on a desktop under 10 seconds (usually due to ghosting on the mouse cursor). So the nay sayers need to learn how to think outside the box for once: 1) It's not because you can't sense it, others are talking bs 2) Stop thinking with "just sight" I personally don't think the human sight is very amazing, but I do believe experienced people can sense minute small differences in things when using more of our senses. Also, in one of the video interviews from Rage, John Carmack mentioned that as FPS increases, input lag decreases. Hence why you'll still see quake players using fps well beyond their refreshrate if they can. Every competitive FPS player will condemn VSYNC as the mother of all evil since it adds a massive amount of input lag.