@hansw@mastodon.social I've been giving it a lot of thought and while circles can be used with groups (it might even work as is, i need to look). But the more I thought about it it wouldnt provide a fully private group capability, let me explain why.

Groups right now are little more than reboosts, however it is defined that way within the standard, basically if your actor_type in the protocol is "group" then a reboost means the same as a post added to the group. But from your perspective as a user/consumer its effectively a reboost with a similar permission scheme as such.

Now permissions in the fediverse for a post need to be considered in that regard. Permissions are a bit confusing because in the client the idea of permissions is not exactly the same as in the protocol. For example "unlisted" is in the permissions drop down but it isnt a permission at all, its a public post that doesnt go out and forward it to other servers. So what permissions basically are is private vs public.. public anyone can get without any encrypted special access. private requires you to validate and is encrypted and all, you basically provide a list of people who have access to it, in that sense a direct message and a circle message is very similar its just circles make your life easier. But it basically just constructs a list of who is allowed to see it similar to how a direct message constructs its list out of everyone mentioned in the post.

So a circle you can think of as a way of creating something like a direct message that lets you give someone permission to view the message as if you tagged them, but without tagging them (so they dont get a notification in the same way you would have in a DM)

So here is the problem.. For a private group people expect the behavior to be such that they can make a post that no one can see except for the people in the group itself. So you want a private message where the permission list is dynamic and changes to match the follower list of a group. that means the permission of the post needs to be controlled by the group server, not the origin server. which means teh post has to originate from the group account and not the user account for that to work at all.

Now you can still use circles, its just circles willl cause the post to only be seen by those YOU define in the circle. There is no way with a circle for you to say "The people who can view this are the members of the group".. all it can do is offer a fixed list of people you give permission to, which may and probably is a subset of the group and may even include people not in the group. so while that **is** useful it isnt exactly able to fill the same function.