Someone who did not identify himself wrote:
You statement was not about the tempo, it was about the speed.
Tempo is a measure of speed, so that statement by itself, without further explanation, is self-contradictory. If you were to have elaborated to say "It was not about tempo, it was about the speed
of the dancer's body" (as opposed to the speed of the music, which is the very definition of tempo), that at least would have made more sense. Of course it would also have been entirely untrue. I never said anything of the sort. If you think I did, you should go back and re-read, because you've missed my entire point... that tempo should not be confused with anything having to do with rhythm, no matter whose rhythm we're talking about.. dancer's or musician's.
Which is to say, that tempo is NOT an applicable measure of the speed of a dance
Exactly. That's to be decided by the dancer, and it can and does vary throughout the dance. Foxtrot in particular is specifically characterized by variety of rhythms. Dancing a weave (mostly quicks) followed by a change of direction (all slows) doesn't make the dancer change tempo... It means he's changed rhythm. The tempo has remained constant. The very statement "the dancer changes tempo" is silly... The word tempo is something we use to describe the quality of the music, not the quality of a dancer. "Oh, yes, Fred... He has great tempo!"
That is why DANCERS often prefer measures per minute - because this gives the APPLICABLE SPEED OF THE DANCE.
Which depends entirely on the rhythm, something your methodology unfortunately can't seem to separate from tempo. "Applicable speed of the dance" can change constantly, because the rhythm can change constantly, but this has no bearing on tempo.
And defining tempo as "applicable speed of the dance" (a definition I have yet to encounter in any dictionary I've read) is inaccurate even if you predetermine the rhythm of the dance ahead of time and never stray from it. Take the example of American style Rumba and Cha Cha, which happen to be of very similar, if not identical, tempi. How does MPM do a better job than BPM of telling you that Cha Cha "feels" faster than Rumba when a person dances to the prescribed rhythm? Either way, the numerical value tells you that the tempo is the same (Both dances are 31 MPM or 124 BPM). So that shoots a hole in your theory that MPM is somehow a more accurate measure of perceived speed than BPM. It's only true
some of the time, and only if you subscribe to the preposterous theory that rhythm is as pre-defined and constant as tempo.
"Applicable speed of the dance" is your own definition. So tell us, what have you determined should be the defining quality of this "applicable speed"? Should this refer to the feet... The more steps you take in a measure, the faster the tempo? Or perhaps the speed of the whole body... The faster you fly through space, the faster the tempo? Or is it a combination of both? And if so, who has a faster tempo: The dancer who travels 6 feet and takes 3 steps, or the dancer who takes 6 steps and travels 3 feet? And what happens when you're holding your position? Has your tempo ceased to exist? Or does it shift to somewhere else... your arms perhaps?
Of course, these are all silly questions, but that's because they stem from a silly definition of tempo. Such silliness can be avoided by understanding that tempo is simply a measure of the speed of the music. Rhythm is something a dancer or musician superimposes on top, affecting the speed of his feet or any part of his body, but having no bearing on the tempo.
Regards,
Jonathan