There are some ups and downs to the Layout feature in assemblies (not the generic layout sketch, the Layout feature with a toolbar button and all).

good stuff:

• can move parts
• make parts right from sketch
• avoid circular relations

bad stuff:

• uses 3d sketch with all of the limitations and difficulties of 3d sketches
• sketch relations seem to turn into mates (?!?!?!?)
• editing it is not exactly straight forward
• requires the use of blocks to get all of the functionality
• fully defined 3d sketch made into blocks is extremely unstable
• part creation from block is not very time saving
• cannot copy/paste from 2d sketch to plane in Layout
• cannot use Autodimension

I feel like there must be something I'm missing here. Has anyone had a positive experience with this feature? Can someone from SolidWorks go beyond the Help and explain what the vision for this feature was/is?