RatherBeFlying:
Messing up the fuel selectors in the Baron crash falls well within the parameters of human error - and is far from the only case where engine(s) quit with fuel in the tanks somewhere and the crew did not figure out why before terra firma got in the way.
This was not a crew, it was a single pilot flying a light twin with a somewhat difficult fuel system, but straight-forward for those competent in the airplane.
The lateral imbalance must have been quite significant well before the right engine "yelled Mayday."