As someone with some musical experience, the ballroom definition drives me nuts. I've seen a show video of Pino/Bucciarelli where they're actually hitting the offbeats. That's a pretty rare example. I'd love to see more cases of musical syncopation in ballroom.
maybe it should start in france:
the french audience is clapping on the down beat, so harry connick jr adds a beat so that the french audience, which doesn't change, is subsequently clapping on the off-beat.
old school hustle music (disco) kept a constant accent on every beat so it wasn't an issue. as such, i would maintain that a DJ that picks music that has onbeat/offbeat feel has merely chosen a bad song to play for hustle.