For me, "Desplazamiento" would be "pop out." The opposite of "pop out" would be "pop in," essentially driving forward from the back foot. I view the pop in/out series is part of the Push + Glide family of footwork as opposed to the Step + Drag - both valuable footwork structures, just applied in different situations. IMHO. Cheers and Thanks for your knowledge
Void step, sounds like some fancy kung fu :) The elbows have a big role to play, imagine that your foot, knee, and elbow all form one linkage. Like a scissor jack that you use to change your flat tire. When you brace your arm during the step back, you bring back your rear elbow which helps you shift weight backward. The same motion as if you're tearing a phone book in half with your bare hands.
