I do not believe ‘signaling’ is an important factor in explaining returns to higher education in general, or to commercial colleges in particular. I believe it declined because economists began to realize that companies rather quickly discover the productivity of employees who went to college, whether a Harvard or a University of Phoenix. Before long, their pay adjusts to their productivity rather than to their education credentials. I agree with one of the comments that such credentialism is more likely to survive among public sector employees.