John,
When we first started doing this monitor stuff, I too, was really skeptical. However, for the most part - it works well. You'd be surprised. The frequency congestion (espicially on 119.3/Rwy 27L.9R), when we have monitored approaches (meaning there is a final monitor and a Tower controller sharing the same frequency), plus having you PROFESSIONAL PILOTS (b/c you are professionals we can almost consistantly know that you're gonna be where you need to be when instructed to do so) check in, didn't really work. There was simply not enough time and space for everyone to get what they needed to say in without continuly stepping on one another. The monitor instruction has proven to work far better than I imagined or argued when it was first attempted. In an effort to try and somehat standardize the procedure, its just been extended to the whole process, rather than one position. Once we got the locals trained, it really has become an efficient operation - and btw, I NEVER thought that I would say that in the beginning. I was very much an advocate of the everybody checks in policy. But I was wrong. On the large scale there are really very few folks who are not on the right freq awaiting their next clearanace...some, but not many. Hope that answers your question!