How to know if a question edit is too big?

Question

Generally on SE sites there are rules about not significantly changing a question after it has been answered. This is a problem because it can invalidate the answers.

This question on Meta is highly downvoted but if you read the answers, you'll see the general consensus is:

Editing the question in a way that invalidates answers or changes the meaning of the question is strongly discouraged. It is allowed for questions that would otherwise be closed, but generally such disruptive edits will be quickly rolled back by other users.

To that end, I flagged a recent question for moderator attention because I felt the edit was inappropriate. I thought that this was the case because:

• It added a third, different example to the question and asked whether that third example was grammatical or not.
• The question had already received five answers.
• The change was not made by the OP of the question.

I'll grant that it didn't necessarily "invalidate" the answers but it did make the answers look incomplete as they were essentially ignoring one of the examples unless they had inadvertently discussed that example previously.

I made the personal choice not to roll back the edit myself because I was not sure I was correct, though my comment about the heavy-handedness of the edit was upvoted and the person who made the edit posted rude comments directed to myself and another user who agreed with me which were subsequently deleted (thanks). After the personal attack, I chose not to roll back because I didn't want to get into an edit war about it, and opted to wait for moderator response.

The response I received was mixed and confusing.

My flag was marked as helpful but no change was made to the question to revert it to the previous version.

Answer 1

The way that I approach this is to first look at the edit comment. Does it say that it is incorporating discussion from the comments or give some sort of other explanation? I came across one instance where somehow the question got asked under a different profile and what looked like a different person editing the question was actually the original author, so I try to investigate thoroughly before I undo or reject an edit.

If there is no explanatory comment and the edit puts words in the mouth of the author, I roll it back or edit it to match what I believe to be the intent of the author. I do leave a comment for the author explaining what I did and that they can roll back the edits to another version if it's not what they wanted.

I may be a little too conservative, because I try to preserve as much of the author's writing as possible while making the question intelligible. I think for those questions where you can see what the follow-up question is likely to be, or that the root cause of the confusion isn't exactly what's being asked, that the right thing to do is to write a comprehensive answer, not change the question. A search returns by default both questions and answers, so I don't see much advantage to changing the question over putting the extra information in the answer.

It's possible that there are times that a heavier hand than mine is needed to make the site the sort of reference we hope it will be for lots of folks, but I let the process work that out. I do what I think is best for the site knowing that if it's not what the group consensus thinks is best, it will get fixed eventually. If I'm unsure in my own mind about what would be best, I ask for help either here on meta or by flagging it for moderator attention. Flags can be helpful to the moderators without necessarily resulting in what you think should happen. I think the "not helpful" status is for folks that aren't acting in good faith when they flag something.

I have yet to find anything I have permission to do here to be irreversible, so I think you should not hesitate to take action you are convinced is the right thing to do, as long as it won't be to upsetting to you if the consensus decides it wasn't. Community moderated and edited sites are tough on me sometimes, because I do get a little invested in my contributions and it's hard to accept that everything I do isn't perceived as perfect :) I try to cut other folks a lot of slack when they get grumpy about me disagreeing with an action that they've taken, because I assume they are just as committed to doing the right thing for the site as I am.