Waiting in Idlewild - yes, Idlewild - Customs hall one day, a Pan Am ( Ahh ! ) Captain approached my Captain and asked if "You's guys did that monitored approach stuff ?" ( BEA, the airline that was experimenting with monitored approach was the other airline that merged with BOAC to form the present British Airways
My Captain said No. Well, said the Clipper Skipper, PanAm has used the monitored approach system since day one. Really ? we replied. Yes, said the Clipper Skipper, pointing to his First Officer - I fly, he monitors.
QED.