To me, having 15 minutes of non-stop, all the same tempo, all the same feel is absolute and utter boredom and I can't see why anyone stays on the floor that long to the same (virtual) song.
Agreed - in fact, if I did that for the group I usually DJ for, we'd be wheeling oxygen tanks onto to floor to help people recover.
I consider it fortunate that I really got into Salsa as I got older, it's really great music, and I love dancing to it. The older Latin group I usually DJ for grew up with it, and even though their minds are willing, often their bodies are not. I usually don't beat match, I often give a slight pause between songs to change partners, and if I see someone(s) struggling, the Tempo slowly goes down.