Genghis when I was learning that manouevre I had the same thoughts but looking into it a bit more it seems that most of these exercises were introduced to develop stick & rudder and planning skills. There's not really much of a practical application for Chandelles, Lazy 8's or 8's on pylons but they're supposed to develop basic skills even if the student isn't aware of it, in much the same way that scale and arpeggio drills do on musical instruments. I guess you could argue that the extent to which they do that is debatable, but then again you could equally apply that to certain things in the European way of doing things.