BD
Interesting point! The original recommendation to the CAA was contained in AIB report 1/89 para 4.13 [page 53 or thereabouts] and followed the horrific airmiss between the Tristar and the Tu154. It said there should be two controllers listening to the R/T [among other things]; however there seemed to be an inference in the wording that might preclude quiet sectors with little or no traffic.