As a B757/767 pilot, and I am sure many of my colleagues will concur, for anyone to take over the controls of one of these jets from anywhere not on a direct trajectory towards the targets, especially if not trimmed and if power is added or reduced, is likely to have had some, even if limited, training on type.
Someone somewhere has probably provided some sort of training, probably in a simulator, wittingly or unwittingly to these sub-humans who have caused this terrible tradgedy. Every training organisation worldwide must go back through their records and see if there is anything that they can find that would point to anyone with a profile that does not fit the norm. I cannot believe for one instant that there is ANY professional pilot anywhere int he world that would perpetrate this kind of senseless massacre whether voluntarily or even at gun or knife point.