I see this sort of thing happen to RBWs all the time, both playing one, and fighting them. I've utterly destroyed people in one round where each hit was a DB, and I've had it happen to me when I fight them. I see more of this actually than any protracted fight with a RBW, truth be told. Either whatever they are fighting just steamrolls them, or they live a couple of rounds and DB does it's thing. I'm not chiming in on the overpoweredness or lack thereof, I'm just saying it happens a *WHOLE* lot more in this way than you are saying.