I've seen so many should-be-a-comment "edits" or "answers" in the review queues by new users, and it's pretty obvious that to them this was the only way to somehow interact with a question due to their lack of allowance to leave a comment. And sometimes (just sometimes) this comment would contribute something useful. So it's a shame to waste reviewers' time to first figure out that a suggested "edit" / "answer" should actually be a comment and then not exactly having tools to turn the former into an actual comment.
If the new user would instead have had the possibility to clearly indicate that they wanted to leave a comment which would then be put into a simple "comments (by low-rep users)" review queue, where reviewers could maybe even leave one of the (more specific) automated comments à la "You should ask this as a
new question" (where
new question might even not only link to the "ask question" site but put the users comment into the title or body). And until approval the comment would by default by hidden by a "on hold" line that only higher-rep users, say >500, could toggle to view (and vote to approve directly in place).
This is typical practice in many blogs' comments, and I think since we're community reviewing anyway this might be improve the hijacking situation.
edit Note that by design those automated comments would not need to trigger a notification to the post's OP but only to the commenter. Whether the un-reviewed comment should already trigger a notification to the OP or not is a different question. I propose not, since the obvious once-in-a-while spam comment would be easier detected by a reviewer who is currently concentrating on specifically determining the validity of a comment. edit2 As noted in the comments these auto-replies should not clutter the original post - once a comment has been determined "Actually I want to ask a new question" they (and the reply) won't show up below the post except for the original commenter who will also be notified if they registered.
- Low-rep user posts a comment -> Below the post there will be a "1 comment under review" link and that comment will be added to the comment-review queue (see images below). No notification will be triggered for the OP, since the high likelihood of an unjustified comment was the reason for comments originally not being post-able by just anyone
- If a reviewer approves the comment, it will show up like any usual comment and now a notification to the OP (and @replied-to users) will be sent
- If a reviewer rejects the comment (with an optional reason as reply), it won't be shown below the original post as "under review" anymore. It, together with the reply, will be visible to the original commenter who will be notified, but no one else will be bothered by it
- edit3 As per Arjan's suggestion: The commenter will not be able to post further comments until their comment is either reviewed or self-deleted. As Tim Post suggested, a negative review/flag should refute that user's ability to comment any more (or reduce a very low contingent of unreviewed comments allowed)