" In the central nervous system, reciprocal relations exist between flexors (bending muscles) and extensors (staightening muscles). The intense excitation of flexors will call forth intense inhibition of extensors, and vice versa. Since the inhibitory process is weaker than the process of excitation, a slight raising of fingers (intense excitation of extensors) before their descent into the keys appears to be a valuable means for strengthening weak inhibition of flexors. The tendency to rush, to accelerate passages is observed mostly among students who are not used to raising their fingers while practicing. Now we see one more reason for requirement of raising fingers in slow practicing. " George Kochevitsky
YOUR COMMENTS......................................................
This is another example of a passage written complete out of musical context, which defeats the whole idea of piano playing. As I have emphasised many times here, the whole mechanism of technical approach is strictly menthal, rather than physical. To clarify this, the music image DICTATES certain technical execution, not the other way around. However, once this image put into pianistical motion, this motion helps to "keep on track" in case of menthal blank-out.
If for some reason the music tells you for some special effect you have to raise your fingers, by all means do it. However, raising fingers as a method taken out of musical context or certain musical idea in my opinion is a dead end.
On the other hand, yes, with my students I make excercises for finger lifting. However, the whole idea is completely different. I will talk about it later, as I have very limited time at the moment. Also, I saw your message in another thread. Will get back as soon as I have some spare.