Can't really rise to that challenge, but I'd say that the distinctive rhythmic devices are lots of 332 groupings (based on the habanera) but the melodic idea that opens the song is like a bandoneon 'sniffing' between each beat - it's just a repeated offbeat accent 1 and 2 and 3 and 4 and. Of course, we don't worry about the counting*, because the numbers are just where nothing is happening. We just step as we sniff (much as I did the other day - I have a cold). *If the numbers bother you, say humbug instead. Never mind that that word has two syllables and doesn't fit. Since when did that matter?