I understand that sometimes when editing, converting, and rendering new videos you can end up with duplicate frames. In other words, two successive frames can be exactly identical.
To what extent can duplicate frames affect the appearance of motion in a video? I've seen the charge that it can make motion appear faster or slower, but I don't really buy this as one frame in a 30 FPS video is only 0.033 seconds. One frame on a 15 FPS video might be noticeable, but again, I doubt it.