We don't mind when someone digs up an old topic, as long as they add something relevent to the discussion.
But, when someone responds and answers a question that was asked 5 years ago, and the original poster hasn't revisited it in a long time, it better to just start a whole new thread.
Lots of times new members dig up the old posts, and then only make a three word comment so they can get their 5 posts in order to be able to post a link or photo.