The StackOverflow FAQ includes a lot of information on how to ask questions and what questions to ask, but very little information on what makes a good answer. I often see answers (example) of the sort that simply reference an external site and say, in effect, go read this. Unfortunately, over time this will lead to answers that are merely broken links as the linked information is moved (or removed). On occasion, I've added comments indicating that answers that link to external sites really need to have a summary so that they remain useful over time. I'd like to see something about how to construct a good answer addressed in the official FAQ along with the information about how to construct a good question.
You can now find the (linked in FAQ) content on writing a good answer at https://stackoverflow.com/questions/how-to-answer