Appendix to "Unboxing":
1) While "White Boxing" reveals the next level as a nested "map", unboxing reveals the entire hierarchy across all levels as a graph (inside the parent map), reversible.
2) Usage hint: before putting topics in a container move them to a suitable position (and release mouse button) *before* dropping them onto a container. White Boxing will reveal the topics on that very positions then.
See DM6 Elm
See also 'Unboxing'. wikipedia