If you want to expand on someone's existing answer (add more detail, provide an example or code snippet, etc.) and have the ability to edit other folks' answers, is it better to add your own answer, or edit an existing answer?
I recently ran across this dilemma in this question. Tim Sullivan posted a nice, quick, correct answer on how to strikeout text in Stack Overflow. However, I figured some Stack Overflow users might not realize that you can use HTML tags in Markdown, so I posted another answer with a code block showing how to do this. My answer, rather than Tim's, ended up getting more upvotes and the questioner changed the accepted answer from his to mine.
Now on one level, maybe this is how it's supposed to work. With the example my answer probably was somewhat more helpful than Tim's. Nevertheless, this didn't really seem fair to me. Before Tim's answer I would have had no idea how to do this, and I was just posting the example trying to be helpful, not answer sniping.
It was at about this point that I realized that I've got edit powers, and I could have just added the example to Tim's answer (I've passed the edit threshold recently enough that I didn't remember). So I added the example to his answer and asked the questioner to switch the accepted answer back to Tim's.
Now this incident got me thinking about the more general case: in a situation like this should those of us with edit powers add our own answers, or edit the original answerer's post. On one hand, people seem to be touchy about having their stuff edited. On the other hand, they'd probably rather not be answer sniped and miss out on potential rep gain. Which is the better course here?
The other thing this got me thinking about is the 2000 reputation points threshold for editing. That's quite a bit of rep (minimum of ten days with the reputation points, realistically more like 2-3 weeks, even for a really active user) and setting the threshold that high encourages people to think of this as more of a discussion forum, rather than a cooperative wiki-type site. As I said, I'm so used to just slapping up an answer I forgot editing the previous answer was even an option. While I'll probably remember in the future, it seems like the edit threshold is pretty important. A high threshold makes this a more competitive, reputation points-hunting, discussion board type of site, while a lower threshold would make this more of a wiki site. Is the editing threshold too high?