Let us not forget the unfortunate crew and pax of a south american DC-8? into JFK a few years ago who were held and held due to wx who did NOT communicate sufficiently their fuel state emergency and crashed !!!!.
January 25, 1990, Avianca 707:
DCA90MA019
They were not critizied for not stating "Mayday" three times, they were critized for not clearly declaring an emergency.
General comment: "Mayday" three times serves a useful purpose in a non-radar ATC enviornment, especially when relay of communications is taking place through ARINC or such. But, in a busy radar environment it serves no purpose other than to tie up the frequency. AAL 52 could not have made their declaration any clearer.