That's the view I'm leaning toward. I went to see one of my professors three times last semester. Each time he sort of shooed me out of his office after about ten minutes. Each time he said he was preparing for his next class.
I kept thinking "what preparation - he's been teaching the same cases for years."
Later in the semester, when i saw a list of publications of faculty, i realized that he probably was actually busy working on a paper for a conference.
I can appreciate the pressure for the faculty to publish but, unfortunately, it can easily come at the expense of teaching the students.
Modern educational theory is that you have frequent assessments on a small amount of material. The assessments don't necessarily need to be graded.
The purpose is to give the students feedback during the course of the semester; it's an opportunity for the teacher to give the students some direction that may be necessary; it gives the students a chance to see if they are on track with the kind of questions that the teacher gives and how she / he wants them answered.
It results in a much more effective learning experience for the student. It is more work for the teacher.
My understanding is that many students - maybe even most, at some law schools - won't get jobs in law firms but that the law degree can open up a lot of doors job-wise that would not be open otherwise.