Look very closely at the following animated gifs:
manipulated these videos?
Question: How do you think I manipulated these videos?
Answer: I didn't.
The bouncing effects you are seeing are what the video clips show when you loop two sequential frames from the videos together.
To replicate, get Vdownloader to grab videos (see links to videos under gifs). Then use VirtualDub to analyze video clips frame-by-frame. The numbers of the frames I used are listed under the gifs. Go back-and-forth between the frames to see the bouncing effect. Note that there are tons of these bouncing effects throughout the video clips.
The question is are these bouncing effects just the result of the normal compression phenomenon that do sometimes happen in videos taken with a camcorder, or are the amount and degree of these compression effects in all these 2nd hit videos abnormal?