Quote Originally Posted by Salty
Yeah overhand right is perfect for going over jabs, it's even better after firing a left uppercut. Left uppercut overhand right is devostating, the uppercut breaks the guard and puts you in the perfect position without having to load up anymore to get great power behind the punch.

It sort of acts like a corkscrew motion to put it best, where your elbow shoots out so it has a slight loop to it allowing you to put more shoulder and hip into the punch. It's one of my favourite punches. Try throwing it when you can predict the jab coming throw it at the same time, when you get it correct the corkscrew motion knocks their jab down and out the way and you can land cleanly anywhere on their right side of their face.
arguello uses the left upper + overhand right combo pretty well. His right really comes crashing down.