Vacchiano used to warn us that some exposed octave lies in waiting somewhere in every piece of music. "Therefore be ready," he said. It was our job to find them and have them ready. Item #2 on our to-do list is octaves of all sorts. (Item #1 was for dim-wits: the diminuendo. See last post.)
How many excerpt passages containing important octaves can you list on your practice menu? To get you started, how about: Zarathustra, Sinfonia Domestica, Death and Transfiguration, Mahler 5 and 7, Sheherazade and countless others. Continue the list and organize them for practice. Prepare them in different keys, rhythms and dynamics. Become an agile and accurate octave machine, an octave-pus!