Can we measure professor productivity?

At Texas A\&M, they are using cost/student as a performance evaluation metric. Predictably the would-be teachers' union is opposed, as are some professors (are these the low-productivity ones):

Some professors express deep concern that the focus on serving student "customers" and delivering value to taxpayers will turn public colleges into factories. They worry that it will upend the essential nature of a university, where the Milton scholar who teaches a senior seminar to five English majors is valued as much as the engineering professor who lands a million-dollar research grant.

Two approaches are emerging. In one, funding is based not on enrollment, but what students accomplish:

Details vary, but colleges typically earn points under such a system for pushing students to take science, engineering and math; for ensuring that they complete classes that they start; for improving on-time graduation rates; and for boosting more low-income students to degrees.

The other is to try to build credibility with the public by disclosing more information:

Minnesota's state college system has created an online "accountability dashboard" for each campus. Bright, gas-gauge-style graphics indicate how many students complete their degrees; how run-down (or up-to-date) facilities are; and how many graduates pass professional licensing exams.

The California State University system, using data from outside sources, posts online the median starting and mid-career salaries for graduates of each campus, as well as their average student loan debt. "Taxpayers can make a pretty good estimate of their rate of return," says Mr. Alexander, president of CSU Long Beach.