I kind of understand that reading and posting in large forums takes longer.
I think the main point is, that most of this happens in the most recent posts. So a speedup can be applied to the first few hundred posts.
Users can be motivated to set the forum to 1 day only, because the get rewarded with extra speed.
Or we really do the archive forum, then we as the admins have full control, and don't depend on the users.
I am just simply thinking of bulk moving all posts from the main forum to the backup forum every day. I think this is a almost trivial program to write.
