Quote - Conventional rigging and W-Mapping are actually doing the same thing.
They tell a vertex to move from position 1 to position 2.
The rigging, conventional or W-Mapping, has to tell that to a lot of points at the same time using a fall off zone..

For elbow and knee bends a "change" to the curve is sometimes required. 

Some creators do that by "painting" on the W-Map. I do..
Some do it by adding magnets.

Poser legacy figures do that by adding magnets.

Unfortunately for us, there are lots of left-right errors in those magnets in ALL Poser figures including the lastest ones.

These 'WRONG" and asymmetrical magnets make it extremely difficult to make clothing for legacy Poser figures.

But, there's a huge difference with a weight map - affected actors.

Instead of conventionally rigging a single joint, you can weight map and rig multiple joints to work together.  So, when you move the collar, you can add the neck as an affected actor so that the neck moves properly WITH the arm, plus the shoulder.  The same is true for the lats, pectoral muscles, etc. 

Weight maps with affected actors changes rigging dramatically.