It's disappointing to come to Meta and find out that a feature I'd really like to have has been shot down in flames already.
I think this will be a burden for the moderator. He has to look into
each and every answer a new user posts and should decide whether it
should be moved to the question or not. When the user group grows to
an enormous one this will be a huge task for the moderator.
Well, tough beans -- I already have to look at the answer because someone has flagged it as 'not an answer' so what's the big deal?
A lot of the old hands have answered from the perspective of long-time SE users who are already familiar with the format. What about the brand-new user?
New users are not so stupid that they post an answer instead of leaving a comment -- they can't post a comment because we won't let them, because they don't have any rep. They can't come into the chat room and talk to us before they post, because we won't let them, because they don't have enough rep. All they can do is plonk their comments down as an answer.
So then the mods have to come in and clean up, and say, here's where the help center is, here's the tour, here's how to ask a question. No matter how friendly I try to be, I'm stuck with the job of telling them you can't be a part of the community without doing homework first. It's unfriendly as hell. Aren't we supposed to play nice?
If I could take these answers which have the seed of a new question in them and spin them off into a new question, retaining the authorship of the person who posted it, it would give them the chance to earn some reputation, maybe enough to be able to use the chat room, where we could talk to them and encourage them to participate more.
These not-really-an-answer posts are going to be work for the moderators anyway. Having the choice to turn them into a comment OR promote them to a new question would give me a tool so I could do productive work instead of non-productive work.