This exercise feels backwards.
It's called Leading string crossing. Here's what it says: "The right arm does not have to move all in one piece when crossing from one string level to another. The hand leads when crossing from a lower strings to a higher string, and the elbow follows. The elbow leads when crossing from a higher string to a lower string, and the hand follows. This is hardly visible during normal playing, and this exercise exaggerates it by splitting the whole-arm movement into two, separate movements."
The first pentagram goes as follows:
1. Play B on the A string,
2. Move elbow to the open G string level, keeping bow on A,
3. Move bow to the G string and play open G.
4. Move bow to A string, with elbow on the G string level.
5. Move elbow to the open A string level and play C.
So the movement as it is noted in the pentagram is B-Elbow-Hand, G-Hand-Elbow, C-Elbow-Hand, A.
The opposite feels more natural. For example, when moving from B (A string) to G move the hand first and then the elbow.
What is the reason to have the elbow move first when moving from B to G, and have the hand move first when moving from G to C?
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