ATC Watcher and all,
I agree with everything you have said. TCAS is (excuse the expression) a bastardized system piggybacked on components not originally designed for use as collision avoidance systems. Assuming that, it works remarkably well.
A “clean sheet of paper” design, incorporating ADS-B or its equivalent and FMS interface will not occur during my career…..and right now, with airline economics being what they are would not be installed unless mandated.
One aspect that is seems would be relatively easy to design into existing FMS aircraft would be a reduced climb/descent rate in the last 1000 feet to prevent (false) RA’s. (Perhaps this is built into recently designed aircraft….I’m flying an early FMS design).
Another apology…this time to HD…..I agree – my statement that if you get an RA, ATC has failed was painted with a broad brush. Pilot error (altitude bust or lateral deviation) that triggers an RA is not the fault of ATC.