Yeah, I got some ideas.
In 2016 if you select a bunch of objects and right click, create group, then if you select that group and right click, you can choose ungroup.
If you create a group as above, then select that group as well as some other objects and again right click and choose group, it will do so.
Now that you have essentially grouped a previously made group with some new objects you will find that ungroup is greyed out.
There are two ways I know of to deal with this.
1. Command QKUNGROUP. Select the group that won't ungroup and type QKUNGROUP. It will ungroup it. That will take it back one step.
2. When you want to add objects to an already existing group, select the group, right click and click Add To Group. Then select the objects you want to add to the group and enter. This method adds objects to the group, but preserves the ability to use the ungroup command.
GChapp