Videos with comments for developing critical thinking and finding best ideas and points.
In the huge labyrinth of information online, critical thinking and an ability to make good choices between information is more and more important. Therefore I have added comments to reinforce critical thinking.
Very good information here is everything about hand positions, mirror positions of right and left hand, pointing out the of independence of each particular finger. Simplification to hand positions and independent finger work. Super!!
On finger, wrist, arm technique I would give just a few comments – it is almost only about speed of depressing keys, not the mass. Why? Your motion and strings are never in direct contact through your body mass. All the energy is conveyed into strings by the speed of hammer motion it is just pure physics. Most of the mass you use actually is just bumping against the bottom of the keyboard and a waste of energy. At the same time arms and wrist give a bigger chance to increase the speed of depressing keys and are helpful for getting a wider sound. There have been experiments with 5 year old kids and sumo wrestlers and they can basically achieve similar sound volume when using the same speed regardless of the mass used.
The other thing to notice – too much bending of thumb can become a problem. He is playing well, still has got some technical issues, that do not let him go to real technical speed and freedom. And I believe part of the reason is his use of thumb. A more relaxed and smooth crossing gives better results in my opinion. Thumb muscles are really big and influence the whole hand. Thumb is sometimes called ‘the lock of hand’. If thumb is bended, it has a risk of creating unnecessary tensions in hand. As legato playing is actually ‘sounding in legato’, not ‘playing connected in terms of physics’, too much physical effort for legato might be counterproductive.