This is the best site I have had the pleasure of visiting.
I am now 76, and a former teen age ballroom class instructor of 1948, and ballroom dancer from 1948 thru 1965.
Your comments are correct regarding the proper beat for the Rumba.
I had the pleasure in 1947! of dancing by the: Miami Beach Rumba & Siboney.
It still holds up, as the true rumba beat (tempi). As my generation says: If you do not have the swing, it don't mean a thing.! And who ever heard of dancing a waltz, by anthing but the 3 quarters of time. (3/4). I was a ballroom dancer 50 year's before the show: Dancing with the star's, and the new fad movie of last year. My most cherished dream is for the younger generation to bring ballroom dancing & the big band era back. You can not have one with out the other.
Enjoy! have fun!, and when you 'slide' on that ballroom floor again, have the orchestra play : Poor Butterfly,/slow fox trot/jive. One more time for the kid of 1948.
Sincerly'
The Ballroom Kid of; 1948
Eddie C.