I have been thinking!!!! At first I completely disagreed with the thoughts of luckyman as I felt that the person involved was knowledgable in his or her field. BUT are we coming to the point where contributors knowledgable in their field just think that it is a waste of time to answer as the topic will be well covererd by that person. Sooner or later AB will be completely monopolised by that person who clearly has time on his or her hands and in my mind might be detrimental to the website. I can indeed understand that someone may be an expert in perhaps one ot two topics, but here we have a multi-topical expert.
So luckyman, in my opinion you DO have a point.