Well forum organization is a huge part of keeping things in some semblance of order. I usually merge/blend posts to keep things on track. It is tedious (but I usually pm the user to explain why it was moved (or I leave a marker). Kept up with many posters get the idea.
You can move it directly below a post, or you can just merge it into the correct forum. Either way works and the caveat is that you have your board organized for when you have a guest that comes in and usually came by a search engine and they can go directly to the forum/posts they are looking for, without going crazy going between 800 posts (especially if your board is active).
Hope this helps..
Dunny
