Sorry, but it’s not useful to just say “Totilas is WAY better through his back” and you “get a feeling” of active suppleness.
What precisely are you looking at that tells you this? Granted, Totilas and Karl’s horse are quite different in their style of movement (I love them both), and yet the lifting of the back is the lifting of the back. Doubtless Totilas is going to win in a competitive arena, but does that mean Karl’s horse is stiff and hollow? Are you SURE? Or are you just seeing what you want to see?
You said you had never seen a horse trained using Baucher’s methods that wasn’t tight and hollow, and asked for videos. Assuming you are actually interested, and not just blowing smoke, I’ll suggest Karl’s 4 dvd set The School of Classical Dressage. Then you can make your own conclusions based on longer and broader videos. He starts with the training of a young horse and goes through double bridle and advanced gymnastics. The last DVD is high school, and includes a video of Karl’s last ride on his GP horse (trained at the Cadre Noir) before its retirement.
Unfortunately for you, these DVD’s are expensive, and apparently have not been pirated onto youtube as of this writing. So if you are really interested, you can spend the money and perhaps learn a little that you didn’t know. Or you can continue to be certain you must be right and anyone who doesn’t see what you think you see must be wrong.