fellow pilots and other aviation lovers:
I think this thread has been a very useful one. While we all seem to fly planes, each cockpit is different. I have never been in a Legacy ( sorry, Brazilian planes just don't do IT for me) and didn't know how confusing some of the displays can be.
In the last 2 jets I flew, the TCAS display was right on the wx radar either as a dedicated display or overlayed to the wx radar when in use. We could select ranges just like the WX radar. When the TCAS went out of service, the display would go blank except for a TCAS operational status readout.
There are other TCAS systems that are the minimum required installations and have so little data, I can't imagine a pilot enjoying it (just on VSI with max range 6 miles or so)
Our old planes did have reply lights on the transponders/tcas . These were so called "steam gauge" instrumented planes.
I think we are seeing what many of us have worried about for years...that the engineers and designers have taken over and the pilot/machine interface leaves us vulnerable in new ways.