If an answer uses a link with the default format (using [link text][1]) and later [1]: http://somelink.com/ then when a moderator does convert-to-comment it doesn't become a link.

It should convert to [link text](http://somelink.com/) without the moderator having to go edit the comment.

Here is the answer text to this question that was converted to a comment:

Hopefully someone else (who knows more about it than I do) will post an answer that describes how trading actually works these days and why the physical stock exchange is necessary. However, the 2010 "flash crash" is a good reminder of what happens when we let computers take over.