pianoloverus Can you tell us which specific passages you tried this on?
FWIW, parts of the sonata for violin and piano by Clémence de Grandval. There are some very brilliant bits of fast fingerwork, similar to the Chopin and Weber examples Hamelin plays in the video.
Hamelin does not mention possible benefits to the RH in the video, but that doesn't necessarily mean that there aren't any. Here are a couple of comments from that video:
@CraigB-tr3rh
2 years ago
We use the same technique in track and field, at least in the throwing events. Try going through all the footwork for putting the shot or throwing discus, but do it 'backwards' with your non-dominant hand, and somehow your good arm feels much more at ease. I never thought of doing the same thing on the piano.
@JuliaPikalova
2 years ago
🎹 It's a really helpful technique not just to develop your left hand, but to learn any difficult passage in a more solid way. The right hand may also benefit 🙂
For instance, my left hand is better in big leaps, and the right hand learns from it the wrist position and hand/arm movements when "taking off, flying, landing". And sometimes I even discover, to my surprise, that a certain passage where I supposed my right hand to be better – is, in fact, easier for the left hand in symmetrical inversion. In any case, in difficult cases I usually find that trying to exercise the other hand symmetrically (together and separately) makes it easier afterwards for the target hand. Bingo ))
A quick search on the Internet shows that there are other pianists who use this technique. It's explained in Exercises for the Piano by Rudolph Ganz (1967), and there's a whole article about it here.
From that article:
So why does this work? We know that the left hemisphere of the brain controls the RH and the right hemisphere the LH. There are connections between the identical areas in both hemispheres, which means that the nervous processes happening in one hemisphere get reproduced in the parallel areas in the other. The proprioceptive sensations in one hand help those in the other.
In addition, science has shown us that the right hemisphere of the brain deals more with spatial awareness, with greater sensitivity to motion and distance, whereas left hemisphere is responsible for linear functioning. So by practising using the symmetrical inversion tool, we can draw on the strengths of the whole brain. The two hemispheres act together to enable a sort of stereophonic knowledge. The dominant hand helps the other hand, and the benefits are enhanced tactile and intellectual memory, because again you are thinking about every single note in its context.
This certainly isn't the magic pill that will cure all known ills, and I don't think I will be making a great habit of using it, not the least because it sounds weird, but it's a useful technique to have in reserve. I think it might be useful as a way of giving a fresh view to something I played ages ago, which is still infected with old, bad habits.