Double rotation

In order to play succeeding fingers, a technique known as double rotation is required. When the thumb is played, a rotation towards the body is instituted.
This holds true whenever the thumb is played:

1. The thumb on the right hand will have a rotation towards the left,
2. while the thumb on the left hand will have a rotation towards the right.

This principle is never altered.

Rotation also assists in enabling the thumb to make it play like another finger. When finger 2 (the index finger ) gets ready to play, it has already been lifted by the forearm in the direction of the already played thumb and now needs to rotate towards the right by means of a circular path. When finger 2 drops, it creates a rotation in the direction of the next note to be played.
Finger 3 is then lifted as the forearm rotates back (to the left for the right hand) in preperation for the dropping of finger 3. Finger 4 is lifted as the forearm rotates back (to the left for the right hand) for the dropping of finger 4, and finger 5 is lifted as the forearm rotates back once more, before it drops into its key.
As each finger drops into its key it brings a rotation of the forearm in support of it, for even though the rotation of the forearm follows the finger as it plays into the key, the finger will play straight down on key contact.

You rotate to play straight, which means the rotation of the fingers and forearm into the key generate a vertical motion. The brain will pick up the action of the finger against the key. Rotation gets the player across the keys (choreography of the keyboard) and the action in the air is not recorded by the brain.

Even though the finger approaches the key on a circular path as a result of the rotation of the forearm, when it reaches the key surface, the motion generated is a vertical motion.
Double rotation should be practiced hands seperately until a feeling of ease and tonal eveness is attained. Care must always be taken that the fulcrums at the hand knuckle (first phalanx and metacarpal bone) and the wrist do not collapse.