Try to post a little more helpfull comments than saying you still have pilots who don't know how to use their TCAS or will try to fly into something. Clearly your knowledge of flying needs a little brushing up.
We don't expect the controller to know when we want to descent or what speed we would like to fly but we would love to know, WHEN he/she WANTS us to descent and, WHAT speed he/she WANTS us to fly - EARLY!!
As I said it all goes about being able to plan so that I can make the ride as smooth as possible for my customers, and with as little typing on the FMC and as little switching on the FMA as possible. This allows us the time to keep our eyes on the TCAS (so that I don't fly into anyone else)as well being able to be heads up, and free to concentrate on listening to and answering the radio so we don't join the gang of Say Again Airlines whilst building up a mental picture of other aircraft, weather and any other factors that could operationally affect my flight.