I came across this today:
Part of the discipline of mastering the Zen flute is learning to deal with the frustrations inherent in learning to play it. That is why much of its study is dedicated to “forging the mind-body” – developing the intuitive, spiritual side of the performer as much as the musicianship itself. Playing the shakuhachi in this context is called suizen, or “blowing Zen”. To blow Zen, one requires great breath control; yet, after years of training and practice, the shakuhachi player strives not to try to control the breath at all. Instead the breath is observed. The player “watches” the breath with a concentration that consumes both the observer and that which is being observed – the player “becomes” the breathing.
This mirrors my experience. There is a lot of frustration in getting the embouchure right and getting consistent sounds from the instrument. But if one approaches the shakuhachi as one might approach shikantaza (“just sitting”) meditation, then that frustration becomes the seed of discovering the instrument, and the relationship between player and instrument. Just blowing; that’s all we need to do. The rest will come.