Quite often we need to have groups nested within other groups, usually to facilitate randomization requirements. Say I have 20 rows, rows 1-15 need to all stay together and 16-20 stay together, but within 1-15 I need 1-4 and 7-8 to always be grouped together. And this is while 1-15 and 16-20 are also randomizing. Sometimes I need to display headers on these groups as well. Overall, this requires quite a bit of custom scripting because we currently don't have the ability to nest a group inside of another group.