Not that you’re looking for anything more to complicate your practice, but I did something fun the other day. Try to play through a substantial portion of your current piece (I was sparring with old Saint Saens) using just one part of your bow. First, I stuck in the upper half for the first two and a half pages. Then I played the same passage using just the lower half. Doing this makes you reconsider how and why you apportion the bow and begs the question: are you using your bow to do things that are beautiful, or are you defaulting to something less? Experimenting with these extremes not only tests your technique, but also opens the ear to possibilities that you may not otherwise stumble upon.