Honestly, these exercises can either be extremely helpful or absolutely
worthless. Regardless of the focus, their purpose is to help translate
all the amazing potential in your brain into attainable possibilities for
your hands and fingers.
Remember that speed alone is meaningless. The passion has to be there,
the accuracy and knowledge have to be there, but speed is just an
'extra.'
Often you'll find that the best exercises come from difficult passages in
pieces that you are trying to learn.
