Some Question Regarding Octaves

Lately i wanted to study classical piano literature again and improve my technique. It has been for so long that i haven't studied any classical piece.I remember i was trying to improve my octaves so i decided to study the closing measures of La campanella that has lots of repeated octaves in the right hand. I think i may have hit a gold mine that forever changed my style. I was frustrated because i didn't get speed but suddenly something came to my concious mind that i want to ask if any of you have experianced. I tried to feel the relation of shoulder and chest and back muscles in the piano playing. I noticed that if one hand is accelerated to the front in the sense that my left shoulder and the correspoding muscle in my back is moving my body in front towards the piano,then the right shoulder can naturally be accelerated to go back and so the right hand can be moved backward. I tried this not only in campanella but in other pieces that do not have octaves and have double notes or single arpegios or fast scales and works like a dream.Now i can't imagine playing any passage without thinking or feeling that i am moving just a little bit in some direction,usually when one hand is accelerated to the front the other goes to the opposite direction. Now regarding octaves i think that the use of interroseus and lumbricals and the desire to have my hand after each contraction in to the natural shape,brings a different grasping action:Grasping with the whole finger (or rather the distal phalange as well as the other two are moved) and there is strong contraction in the top of the palm. I have posted a small video of me practicing those measures. In the video it may not be seen but i was moving the right hand towards me and the left hand towards the piano by the shoulders and the back muscles.Is this correct or no? (i was playing something other in the end but forgot to cut it!)

The way you DESCRIBE it is great. But what I see in the video is not so easy to judge. Perhaps you play better when you have this inner feeling than otherwise, but we don't have a comparison video to ascertain this. I would say your left hand sound needs much more body, especially the bass notes. Your right hand is really brilliant but is not balanced in sound by the left, so the result is a little shrill and thin. If BOTH of your shoulders felt like they dropped forward (of course, you can't really continually drop them forward because you would crash into the piano), then the stress would be taken even more off the hand - your hand cupola needs to be more "supported by air from the inside" and less "stood upon." And the use of the body you describe, if you did it even more, would help this happen. Thanks for an informative post! AFF