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Sorry if this has been asked before and has some ranting in it, but I'm beginning to feel fed off by robo-approvers.
This week happened at least ten times to me: I carefully reviewed an edit on a long or contrived post and then decided to reject the edit for various reasons (usually "too minor" or "invalid edit"). When I clicked on the "reject" button the dreaded red box appeared, telling me that the edit had already been approved! The annoying thing is that, while we may have different thresholds for what is "too minor", blatantly invalid edits passing reviews are really a bad thing (did you ever see an edit with a "fixed gramar" comment and lots of unresolved spelling and grammar errors – even in the edited parts – being approved!?!).
The problem for SO is evident, but the problem for me as a reviewer is that I wasted at least 5 minutes on a review checking for wrong changes, missed editing opportunities (i.e. the editor didn't correct all spelling mistakes, etc.) coherence in overall formatting, etc. Multiply by ten and this week I wasted almost an hour for absolutely nothing, so I find it ever less rewarding to do exhaustive, high quality, reviews.
Moreover this is slowly turning me into a robo-rejecter: if I spot even the slightest hint of a problem in an edit, I feel the urge to click on reject for fear that some robo-approver enters into play. And this, again, is bad for SO because I risk of rejecting an edit which could have been good if examined in detail, or could have been easily improved. Net result: me doing a bad thing and the editor wasting his effort – quality editing loses, robo-approvers and lousy editors win!
The easy solution for my personal case is clear: stop doing reviews and let the robo-approvers lead the field. Of course the problem is for SO overall quality: robo-approved edits means more user gaining rep by only doing bad edits, and these users will probably become robo-approvers as well when they gain the privilege: even if in good faith, they never learned how to judge whether an edit is good, so they will likely be approving the same things they were allowed to do in their past.
I think some sort of short-term locking should be implemented. For example remove from the review queue a post that's being reviewed. If the reviewer doesn't make a call in reasonable time (10 minutes?), put the post on the queue again. Of course this would slow down the reviewing process, but this doesn't appear to be a problem, except for the close vote queue. Another mechanism could be to disable all buttons (except "skip") – or only the "approve" button – until some time has passed, and the time should be proportional to both the post length and the amount of changes (how can we trust a reviewer pressing "approve" after only a couple of seconds when he is faced with a 100 line post which has been heavily edited?!?).
Mine is not a clear-cut proposal, so I didn't tag it as a feature request. Devs or long term users know better what mechanisms could/should be implemented.
My point is that if there are many reviewers sharing my feeling on this, then some mechanism should be implemented!