Patent valuation through frequency of citations

Eva Lehnert (IFPI) has drawn our attention to this piece in Business Week on assessing the value of a patent by the frequency of its citation in patent filings: it's "A Powerful New Tool for Patent Valuation", by Chi-an Chang. While this is a good idea, she says, it depends on the details of the patent filings and the willingness of the applicant deliberately to attract attention to prior art which might get into the way (one of the comments posted regarding this article refers to this stumbling block).