Thank you for your reply, lelle!I have been doing some research on injury and a post mentions "static muscular activity" as one of the causes. I then realize indeed when I practice, I often forget to release after pressing the keys, as you say, "forceful movements". I find playing soft passages very difficult and requires a lot of *efforts*.
I have a Roland FP-30. Fortunately it is with weighted keys. With the grand piano I am able to *feel* the lever and watch the hammer while touching the key and hear the dampers as I release. The visualization and sounds are not only amusing but also help with control. A huge difference is the pedaling. My pedaling is really not good. Yes, need to be patient!
I was wondering what your experience of suddenly playing a grand was. Was it difficult and overwhelming or did you feel well prepared?
Right wrist seems low and hand too colapsed, think of and arch, holding a ball in your hand. Try higher wrist and get more power from arm/shoulder, and then you relax fingers more inbetween notes, more hanging hand. I can see the hand tense up. How are your seat position, posture, we dont se that from the video? Relaxed neck/shoulder not?