Consider this answer, which appeared on my low-quality queue. A user (ibid) commented a very good link backing up this answer. I then started to edit, but realised afterwards that I had completely changed the answer.
The old post:
I haven't done any research on what house she is in but my friend told me she is in Hufflepuff.
My edit (That I have not yet posted):
In an old BBC interview from 2000, JK admits she took a fan-made quiz online and got the result of Hufflepuff.
Is that a danger with the internet?
The Internet! Twice I've been on the internet. Friends of mine were telling me what's on there and I'd never gone looking before. First time, I thought I was never coming back, it's too scary. Some of the stuff that's out there is very weird. Second time I went in there someone had set up an unofficial fan site where you can be sorted, they have a Sorting Hat, and I was Hufflepuff. I wasn't that pleased! If anyone's meant to be Gryffindor, it's me.
I realised that in editing the answer to incorporate the link, I have effectively deleted the user's original answer and replaced it with my own. Is that the right course of action? Should I edit a low-quality post to the point where it no longer resembles the old post, or should I simply recommend it be deleted?
How much editing is too much?