This NTSB recommendation comes as no surprise in the course of this investigation. However, I believe it to be of little value in the ultimate solving of this accident investigation.
I am not privy to the upset training program at AAL, but it is hard to fathom that any professional pilot would manually enter the abrupt and contradictory inputs mentioned to date. Keep in mind that one of the suspected culprits in this accident is wake turbulence. Wake turbulence at the angles/aircraft types involved normally produces a rolling motion, not normally compensated with by rudder input. At the altitude/speed these events occurred, normally a pilots feet are on the floor, letting the yaw damper system do its job.
One aspect of this accident that I have not seen particularly addressed is that the forces/stresses on the vertical stabilizer/rudder (yaw axis) of large twin-engine transports is (my opinion) greater than other transport aircraft. Vertical stabilizer and rudder area (and therefore the stresses involved) on large twins is disproportionately greater than on other transport aircraft because of the need to keep the aircraft tracking straight with loss of very high thrust engines at a critical time (V1). Not until the advent of large, high powered engines was this situation encountered. In normal operations, this is routinely demonstrated by the relative “sporty” nature one must approach a crosswind takeoff or landing in large twins. These aircraft are weathervanes and take a large amount of control input to counteract this tendency.
Any engineering types out there care to provide more insight into this?