@fugu13  I took that interpretation of the member list to apply to ad-hoc groups only, and to be the reason member lists didn't make sense (to me) in identified groups. I can see the logical consistency of the approach you describe (and the starting point before this PR), but I have to sleep on the implications.

I am concerned about the impact on including identified groups in ad-hoc groups -- the only problem with doing that is identified groups that can contain members are really just a special type of ad-hoc group, so that could get out of control with nesting. If enumerating members was not allowed, it would be fine to do. It seems like there would frequently be value in creating ad-hoc groups based on named groups, eg: marketing, support, and development attended the meeting. Might it make sense just to say that ad-hoc groups may not contain any groups with enumerated members?