I just watched a DVD last night from the horse video club I belong to-- http://www.barnsweetbarndvds.com/index.php --and it was wonderful. It was called ELEGANT DRESSAGE TRAINING and it's about the classical dressage trainer Anja Beran and shows her riding many of her horses. Most are Iberian horses, but not all, showing that her techniques work on all horses. What impressed me the most was the demeanor of all of the horses: they were doing upper level maneuvers, and they were HAPPY, HAPPY, HAPPY! No pinned ears, no tail switching, no heads behind the vertical, no tight nosebands. Her horses were doing elegant piaffe and passage on a slack rein, with ears flicking back and forth from a happy forward to a sideways "listening".
At the end of the DVD was a segment about the transformation of a gelding named Flamingo--Trakehner, I think--who went from an injured, lame horse that mistrusted humans to a nicely-muscled, nicely-moving horse doing a perfect piaffe, way back on his butt, in a snaffle with a loose rein.
I also have Anja Beran's book--CLASSICAL SCHOOLING WITH THE HORSE IN MIND--and the way the book was written indicated that the DVD would be good, too, but even though I was ready for it, I was STILL impressed.
I watched the 1st of her DVDs, and a 2nd and a 3rd will be coming out next month. I've already got them on my rental queue and I can't wait to watch them. I may have to actually buy them to keep in my equestrian library, they're that good. After hearing Beran say that piaffe is a wonderful exercise for any horse, not just an older, more educated one, I think I'll teach my 4 year-old filly piaffe sooner rather than later. :)