A series of new policies in the humanities and the social sciences at Harvard University are premised on the idea that professors need the ticking clock, too. For the last two years, the university has announced that for every five graduate students in years eight or higher of a Ph.D. program, the department would lose one admissions slot for a new doctoral student. The results were immediate: In numerous departments that had for years had large clusters of Ph.D. students taking eight or more years to finish, professors reached out to students and doctorates were completed.
No exceptions were made, and Harvard officials believe that their shift shows that there is no reason for a decade-long humanities Ph.D.
Here is more, I would say only that they did not go far enough. You might think that this causes a lowering of standards, but I’ll predict that the people who leave sooner are no less smart (do some of you wish I had written "stupider"?) or accomplished than if they had stayed longer.
Elsewhere from InsideHigherEd.com, here is a study of economists and plagiarism.