The " people " who installed the original Br. syl. did it with one specific intent--social style only .
The medal test system was modelled on the English system and was added at a much later date .
Idea being ,the average person had the facility to dance with most anyone, doing a like/same movement NOT of the competitive nature . It also was catering to a clientele that were , by and large, the over 60 crowd .
Niteclub outings by studios were a regular occurence,and the syllabus reflected this type of dancing .
Amer. Br ( nor silv for that matter ) was ever intended for that purpose-- this was partly influenced ( maybe largely ) by the Harvest Moon Ball, one of the oldest Comps in the world held in Chicago .
When I first got to the states, the number of comps being held at that level, were primarily in the chain schools ( many in house ) I was instrumental in activating an intra studio comp. which was met with great trepidation by the owners ( what if my students lose ? ) need less to say, they turned out to be very successful .
The numbers grew nationally over time and pro/am was the reason-- hence the Bronze took on a completely different role than was its original intention.
The Br. was revised dramatically to provide much more variety, and yet stay in context with its premise A little " continuity " styling was added as a prep. for Silver .
tango again, was the " odd " ball . it fell somewhere in between T/A and the then Eng. style.( the gold levels have numerous Intern fig )
The Rhythm category, had a much more circuitous route .
Square Rumba is still part of the Amer. syllabus as is Bolero .