I don't know how you can't notice it when doing video editing, you have to actively notice the frame rate to do it right. Any choppiness will be evident. Also I really don't understand your second paragraph. You can't get rid of input delay or make frames appear faster by disabling vsync. When you mux the video you target a specific frame rate, the common formats are almost always 24, 25, 30, 60, or multiples of those. The frames are appearing the same, it's whatever is in the video file.