In 1980 he was officially Europe's second best older horse, and the fourth best overall with a rating of 129, placing him behind the three-year-olds
Moorestyle and
Argument as well as the four-year-old
Ela-Mana-Mou. Following a "recalibration" of historic ratings in 2013, the ratings of all horses in the 1980 classification were moved down by four pounds, giving him a new official rating of 125. The independent
Timeform awarded Le Moss a peak rating of 135 in 1980, making him their highest-rated older horse and the second best horse of any age behind Moorestyle. They described him in their annual as "a powerful, relentless galloper......a phenomenon among racehorses: he's not the best long-distance horse we've ever seen, but if there is such a thing as a top-class racehorse that stays forever, Le Moss is probably the closest to him we have encountered since that great out-and-out stayer of the mid-forties Marsyas II, and on the score of determination and courage, precious few stayers of the post-war era rank with Le Moss......His performance in winning his second Gold Cup was one of the most stirring seen on a racecourse in many a year; it was an unforgettable display of endurance and courage......When he took the so-called stayers triple crown as a four-year-old he became the first horse to do so for over twenty-five years, and no other horse has completed that notable treble two years in a row. And he achieved his second treble the hard way, making virtually every yard of the running in almost seven and a half miles of competition......In terms of merit, we rate Le Moss (135) higher than his famous brother
Levmoss (133)." In their book
A Century of Champions, based on a modified version of the Timeform system, John Randall and Tony Morris awarded Le Moss a mark of 133, which put him equal-95th in their list of the top 200 British and Irish-trained Flat horses of the 20th century, rating him superior to nine
Epsom Derby winners, including
Golden Fleece (132),
Royal Palace (131) and
St Paddy (132), multiple classic winners
Assert (132) and
Balanchine (132), triple crown winners
Diamond Jubilee (132) and
Rock Sand (131) as well as
Prix de l'Arc de Triomphe winner
Carroll House (131). ==Stud record==