If #group2 was nested inside #group1 and #group1 was disabled then #group2 would be disabled also (even if it's state was set to enabled). Having nested groups would mean that you could have an entire block of code and switch it all on or off with a single group (regardless of the state of groups contained within), but also enable/disable peices of the code within that.
I guess $group would need some new properties - maybe a .astate property to find whether an ancestor group is disabled, a .parent property, and perhaps an optional second parameter N to get the Nth child group.
