I also re call it being in East coast swing.?( fifties ). It pre-dates most of todays named variations in Salsa .
It was, to my knowledge , never used in Mambo, so I,m guessing someone decided to " purloin " it from another genre .
But there again, many of the variations in Mambo / Salsa came from other dances .
Most dances are hybrids, if you go back to their inception.
The on 2 style, . that all the studios were teaching.And she couldn't be refering to ET, he wasn't even relevant or around as a teacher at that time, nor NDCA
In many Club scenes in various cities, one could often find teachers who were improvising and adding their own "take" to that of the more regimented studio dancer . Even tho we had a strict list on what to teach , we all implemented to some degree, in our leisure time .
When one examines the variety that is in existence today, its not too difficult for those of us who have been teaching/dancing thru that time period, to recognise that, the great majority of variations have a strong basis in the older B/room styles of Bolero, Swing and Mambo. Many even identical