To a large extent the videos will still be useful - the difference is that there's only one weight map for each joint, so if (as is usually the case) the twist needs to be different from the rotations you want two bones - one for the bends, one parented to that for the twisting. To create a figure like this you set it up in the usual way - using TriAx if you are starting from an OBJ in the Figure Setup pane - then with the Node Weight Map Brush Active go to the Tool Settings pane, Binding tab, set Weight Mapping Mode to General and General Weight Mode to Dual Quaternion. However, you don't have to use general weight - TriAx is still there and can still be used if desired.

Quaternions are mathematical structures for handling 3-dimensional rotations in a way that can be combined commutatively, as I recall (standard rotations give different orders depending on the order in which they applied).