I've just rolled back part of an edit to thisthis question that got approved while I was writing a edit rejection.
The edit was approved even though the edit made changes to the original question's code (well list of commands... you know what I mean!). Surely the person asking a question knows better than any of us what they did or didn't do?
Not sure if I'm right or wrong and love to hear what others think but this is how I see it: if you see a fault in someone's code/list of commands/output then, as a matter of principle, this shouldn't be edited in the question but rather posted as a comment or - if the problem seen within the code block explains their fault - an answer querying the mistake.