Interesting video. I think I had the wrong idea about jerk baits, but I have never used one or built one.
The video does demonstrate how the swim angle is relative to the retrieval speed, and backs up the argument that every lipped lure has a hunting speed, but this is just a side note.
It looks like the most erratic action occurs when the lip is vertical, this too makes sense, as it is in this lip attitude that the hunt occurs.
I guess it is nice for the lure to 'spring back' to horizontal, and for the lure to have a nice movement on a steady retrieve, but I think that these are small bonus features to the main event.
Dave