Today I'm going to bring you awareness to the way Illustrator treats groups in compounds.

For me it sounds strange already — why would I want a group inside of a compound path?
What would I use it for?
Ai won’t allow me to go isolate this group to edit its components.
Ai would not show it in the Layers tree —for some reason we can’t expand a compound path to see its children, like we can do with the groups.
Ai won’t give scripts a way to see these groups inside of compound paths — and this leads to problems when you have to cycle through a path’s children.

Still, Ai allows to create groups in compounds.

The very first option, when you select a group and command Create Compound Path, is fixed — Illustrator ungroups it for us it seems ant then create a compound path — if you uncompound it, you would get objects ungrouped.

The second one is simple as that, but is not fixed.
Create a new compound path from two or more objects. Leave it.
Create a new group from whatever number objects. Cut it.
Isolate…