The issue with supervisors as telecommuters is simple. Most supervisory jobs are somewhat unstructured and the schedules harder to predict; thus, it's harder (but not impossible) for a supervisor to be out of the office on any scheduled, routine basis. Supervisors and managers have always had, and still have, the option to take an occasional day at home, but doing it routinely gets harder.

It also depends on the nature of the group being supervised. The supervisor most likely to telecommute is one managing a relatively small group of relatively senior staff who can work independently and don't need as much ongoing coaching and presence from the boss in the office.