I get what you're saying Andre. The way i see it, the elbow coming up is just the natural result of a shoulder roll. I've noticed when Mayweather is backed on the ropes and his opponent is trying to swarm, he'll do that really exaggerated back and forth rolling, and i think as a result, sometimes his elbow comes up unintentionally (or intentionally) and acts a deterrent or a post to keep the opponents off.

I say you shouldn't look to use it, but its an invaluable tool, not just against swarmers, but any style up close.