Steve, your videos are excellent, and as somebody noted in your slipper clutch video, you are excellent at explaining. Thanks a lot for taking the time to do this and post the links here.
If I may, I have a suggestion for improvement: when you want to show a detail of some part, just make a picture really close up, a macro shot, even, and put it in the video when you edit it. That'd help a lot since it looks like your video camera has a limited amount of optical zoom, and when the digital zoom kicks in, the quality (read "detail") gets poorer. This happens in this video at 1:35, for example.