I think you're looking for something that is not there Old Akro, Presumably in order to produce the same outcome, we are talking about an FCU failure that produced an over torque on the left engine. I'm not sure that rudder boost would work in this condition but lets say it does and ques the pilot to apply left rudder. We would expect the flight path to veer to the right, we know by eye witnesses that it went left from rotation.The aircraft should still be quite controllable, accelerate quickly and climb away, unless he realised what was happening after applying left rudder trim, (I doubt you would need all of it) and pulled the left power lever back to flight idle, that would cause a huge yaw to the left, loss of performance and loss of control. It's more likely that the rudder trim was already in that position from the start of the takeoff run. I can't think of any other FCU fault that could cause the same outcome.