My goodness, it's not a private conversation in this context. A conversation is private if it's within a close context, the conversation module can be considered generally private thou but not a public timeline. In this case, the conversation module is not involved but the timeline module which is driven by general comments to post.

In any case I could still see the comments whether or not it is served as a new post. This primarily just help populate comments as post, it doesn't change the privacy of comments.

For instance, a much robust framework is used on Twitter for tweets and retweet, so it's all about what is useful for your site and you can simply turn it off if you don't want it Houstonlively