What law departments could gain if they shared evaluations and data about law firms

I have speculated on how groups of law departments might share confidential evaluations they make of law firms (See my post of May 14, 2006.). Multi-source data would enable contributor departments to manage their external costs more effectively. What are some metrics-based conclusions general counsel might draw from the larger collection of data?

For common services, law departments could compare average burn rates (See my posts of Aug. 31, 2005: litigation burn rates; and Feb. 20, 2006: burn-rate calculations.).

Law departments could surface violations of discount agreements or most-favored client terms (See my posts of Oct. 30, 2005 and Nov. 21, 2005: most-favored-nation terms; Nov. 13, 2006: hourly rates only; Jan. 25, 2006: least-favored terms; and Jan. 20, 2008: my article on them.).

Departments could calculate effective billing rates more reliably with a larger set of data (See my post of June 13, 2006.).

Departments could detect patterns of leverage, or the lack of leverage, and their cost consequences (See my post of Dec. 11, 2007 on leverage in European law firms.).

Departments could analyze disbursement rates with more reliability, given a larger data set.