A gutsy law department could say, for new matters familiar to it and a trusted law firm, “We will pay you what we think each month’s work was worth AND we will explicitly state why we gave it that value.”
Would law firms daringly accept those terms? They should, because it pushes law departments to define value and firms will be able to calibrate their investments of time and staff accordingly.
The final part of the arrangement would be for the law department to say:
“Do not tell us how many hours anyone devoted to the work, just tell us what you accomplished.” This pushes law firms to justify the benefit to clients of what they did irrespective of hours billed.