From http://www.mmguide.musicmatch.com/album/work_classical.cgi?WORKID=016856&TMPL=long&type=cl:
"The history of Debussy's celebrated waltz "La plus que lente" is an engaging one. The composer kept on his mantelpiece a small sculpture by Claudel entitled "La valse," and so skilled was its creator "in transforming rhythmic movement into mass," writes Paul Roberts (in his book Images--The Piano Music of Claude Debussy), "that one has the impression of being able to touch a waltz, of experiencing its essence in another medium." Like Ravel, who saw the waltz as the touchstone of decadence, and in La valse used it to suggest the inevitable collapse of imperial Vienna, Debussy was fascinated by the waltz form as much for its human and social implications as for its purely musical ones. Whereas in Debussy's virtuoso piano piece Pour les octaves the music expresses the inner meaning of the form -- in Roberts' words, "its energy, movement, and line, and its power to excite and take the dancers out of themselves" -- the intentions, and indeed the effect of "La plus que lente" are quite different. The title might be translated into English as "The Even Slower Waltz"; at the time it carried subtle connotations beyond the evocation of a popular style. "La plus que lente" appeared soon after the publication of Book I of Debussy's Preludes, in 1910. It represented Debussy's laconic reaction to the pervasive influence of the slow waltz in France's coffee-houses, dance-halls, and salons. But, writes Frank Howes, "'La plus que lente' is, in Debussy's wryly humorous way, the valse lente to outdo all others." Apparently Debussy handed the manuscript of this piece to the gypsy fiddler Leoni, whose Romany band played to great popular acclaim in the ballroom of the New Carlton Hotel in Paris. This was almost certainly here that Debussy got the idea for the work in the first place. Perhaps the composer was deliberately aiming "La plus que lente" at a less sophisticated audience than he normally wanted to address through his music, but it contained a vaguely condescending Stravinskyian irony that a hotel audience might or might not have detected."
