I'm not sure my own answer to this guestion is correct:
When to post to "Extended Circles"?
When I wrote that question and answer, I thought that sharing to "extended circles" would actively push my posts not just into the streams of those having circled me but also into the streams of those who've circled them. That can't be right, because clearly there would be a large amount of posts in my own incoming stream from people I haven't circled. So what correct, then?
Is "extended circles" actually a narrow version of "public"? "Public" doesn't push my posts to anyone's streams but it makes the posts visible to anyone who comes looking.
Am I right in assuming that "extended circles" also doesn't push my posts to anyone's streams but it makes the posts visible to anyone who is in a circle of someone whom I have circled?