I was wondering this myself; I had only given the monk a cursory read, and in my mind I could easily see both interpretations; either full discipline means that you need to focus on a single technique on your turn, or you can only use a power for a single use on your turn (e.g. move with one, attack with another).
I'm glad it's the first case; it seems easier to work out and avoid problems, and it's probably rather beneficial because the movement mode and attack mode were designed together.