What Is an Ambiguous Backfield?

Ambiguous backfield is really just a way of saying you generally don't want to get players who have teammates with locked in roles in their offense. It's not that they can't exceed expectation, it's that it's historically been very difficult for them to be league winning players. Kareem Hunt, Melvin Gordon, Alexander Madison, Jamal Williams, Nahim Hines, Isaiah Spiller, Rashad White all had early round teammates. Those players are doing just fine from the middle rounds and none of them had teammates going before them.