Editing of grouped controls in v17 is great, but is is difficult to know how are things are grouped. Some ideas to improve this feature:
0) Allow double-click of a group to enter it, not just double click of items within.
1) Blur or gray out layout content that is not part of a group after entering a group for editing.
2) More complicated: adorn items in each group with an indicator (colored letter perhaps) unique to the group.