Even if the video were very very clear, it would be hard to tell exactly what Yamaguchi is doing.
Yes the quality leaves a lot to be desired. Also the subtitles are a little distracting, by reading the subtitles I am missing what is going on. There is a lot of material there, but it is hard to see what he is doing internally.
I am on my second viewing - I think I will need another 2-3 more before I can get something really concrete out of it to apply to my Aikido