It's pretty much mandatory, Gelugon. Allows you to skip the fights you don't want to engage in, and offers you a safe way to go afk, if you need to do so. Just park your character up high beyond the attack range of the Mobs and you can go do whatever you need to do. Can be handy, if you're getting low on HP and don't have any expendables or healing powers. Just fly straight up and out of range. Due caution should be exercised though, some mobs do have abilities which can drop you out of travel mode. And it's a long way down.
