FlightDetent
I think you are referring to FAST - Final Approach Spacing Tool.
I don't know if it is working or has been tried, but I doubt it would work any better than the (highly trained) ATCOs eyeball.
HEATHROW DIRECTOR
You'd be amazed at how little some pilots understand about ATC. I have been told that at Heathrow the controllers start at BNN and take one aircraft off each stack going clockwise!?.. I replied that actually it is anti-clockwise.
G W-H