I borrowed the concept of Baguazhang and implemented it in FMA. To many purists, this is sacrilegious and blasphemous, LOL! But I thought that, Baguazhang's footwork fits well with the continuous hand motions of FMA, hence the mixture. The approach is simple: To continue the attack to stop the threat, even though they have their back facing you. It might be cowardly to do so on paper, but deep in the martial world, a lot of spinning attacks come with a caveat of showing your back. Spinning backfist, spinning elbow, back kick, back sidekick, even a reverse blade thrust. Majority of the training that we do is fighting opponents head-on, and when they turn their back, we stop. In the real world, especially in self-defense, that is probably the most dangerous thing that you can do, as stopping might give them a momentary breather to attack you and turn the tide, stripping you of opportunity.