I'm wondering: does doing exercises of the book Finger Fitness - The Art of Finger Control by Lorraine C. and Gregory G. Irwin really help to increase finger dexterity and flexibility and is it useful for guitar players as suggested in the description?
You will be able to master your finger control and tune your brain in with the movements of your hands. This hand control is critical if you are a musician or magician in need of delicate and subtle hand/finger movements.
There are also YouTube videos available for some of the exercises.
So I'm wondering: does practicing these exercises really help guitar players? I'm asking because I want to practice them if they are actually useful.