I'm with Richard. The database of available information on a board varies as people come and go; just because a topic has been discussed before, doesn't mean that everything of value has been said about it. Old discussions, especially good ones, are excellent to reference into a current thread, but more on the lines of, "This is what we said before, what new and different information do we have now?" rather than, "This is the definitive discussion on this point. Read, and forever hold your peace."
I personally have learned really valuable things from repeatedly discussed topics, as new people come to the board and offer their insights.
I personally have learned really valuable things from repeatedly discussed topics, as new people come to the board and offer their insights.