Oh really...?
"I have always been aware of the risk of a doublet. However, the aircraft is certified for a FULL input at all speeds (suitably limited by the RLL) just not a full input against a sideslip. So a full input should be allowed coordinated with the rudder."
Ah, well actually Wino, this ain't true, at all.
Since the very early days of 707 certification flying, pilots
then had a proper well founded knowledge that large and particularly rapid rudder inputs at higher speeds can lead to severe problems....and this knowledge was passed down to respective carriers who ordered the aircraft, including American Airlines.
Now, one could ask, how come this knowledge is somehow forgotten now?
Plain and simply, the older guys have now retired, and young turks are in charge in the training department, so these folks have NO prior knowledge about the problems that can occur, and further, have NO inclanation to find out, either.
I suspect it is the AA idea of..."we know best, so shut up and do it this way."
Additionally, large jet transport aeroplanes can NOT be thrown around with wild abandon, as some light highly maneuverable aircraft can, at maneuvering speeds, without overstressing the structure.
Positively KNOWN a very long time ago, and American Airlines, and specifically their ill-informed training department, are sadly unable to grasp the facts.
AA mindset, demonstrated at its worst.