This feature concern sites with edits review.
I have been reviewing edits on SO for a little while now, not long as I got 2k rep about a month or so.
Already I see plenty of bad edits... but sometime I see edits that are missing a few things by the same user, over and over.
I tried to tell one that was on a edit roll to make better edits using a comment @username. He stopped after my comment but saw him at it again today with edits that are near good (didn't remove thanks, missed a few spelling errors or formatted things that didn't need to since it wasn't adding to the question/answer).
Other users make formatting changes but nothing else. These changes are good, they make the answer/question more readable but they haven't took the time to actually edit all the other things (remove thanks, spelling, etc).
I'll like to have a more formal way, other than a comment, similar to this flag reviewer proposal, that would send them a message in their inbox with a link (all we got at the moment is the review privilege help page) telling them that a reviewer(s) saw their edits and that they should take more time to edit the question/answer in the future.
Maybe this shouldn't be left in the hands of 2k+ users, maybe in the 10k tools but that leave reviewers like me that want to warn editors that they should do a better job either trying to do it with comments or flag one of their post and take moderator's time to check their edits (which I do once I see a few near-good edits from the same user).
Another option would be to send that message when 10, for example, of their suggested edits received 2 reject votes while still being approved... I'm not certain there's a metric that could do a good job at detecting editors that could use to be hinted that their edits just need a little more work to be of great value.
After a while, I'm rejecting their edits but there's enough people that approve about anything that the message (rejection) won't pass.
Improving their edits over and over doesn't help the editor to make a better edit in the future. It wastes reviewers time more than needed.