Using only aileron inputs (sufficient according to the NTSB guy) was not enough on a heavily-loaded 747-400 on departure from San Francisco (SFO) years ago. While an engine surged/had numerous compressor stalls etc, rudder input was required to compensate for too much yaw. Using more than a small amount of aileron also extends flight spoilers, which decreases lift.
Do all NTSB investigators have no pilot experience, other than in planes with centerline thrust? If so, their specialties must be very compartmentalized. Which investigators have broad enough aviation experience (as a pilot), to realistically determine the primary cause(s)?
