Team MMA anyone? I quite like this concept as it brings in the tactical dimension of multiple enemies. While it all begins one-on-one, notice how quickly the ground becomes a really bad place to be once another member from the opposing team gets involved. The barrage of blows from the second person renders looking for submissions ineffective.
We do drills like this in the club all the time. It gets even more interesting when you have more than on team, with differing numbers in every team i.e. 6 vs. 4 vs. 3 vs. 1. The correct selection of tactics is key and it helps break beyond the limits of one-on-one. Definitely a good drill, but whether is could catch on as a spectator sport is another matter :-) It ends quickly and there is a lot happening all at once; neither of which are likely to give the audience what they want.
An interesting idea though!
All the best,