I guarantee that I am not a high level ambidextrous person, KMN. You're comparing seperate complex motions (one arm performing a task while the other performs another task) to a complex upper body motion (limbs working in concert). Obviously the human body can do the latter: we do it all the time with our legs. We do it often when typing, playing instruments, etc.
You mention modern flight controls, without realising what that really entails. In a modern F16, the pilot deals with (just on the stick and throttle) SEVEN axis directions, plus five different four way hats, a two position trigger, six different buttons. You're going to tell me that they can't handle a pair of sticks? There's a mini-stick on the throttle that is operated by the left thumb. There's an directional antenna knob, a range knob, a radio switch, airbrakes, dogfighting multi positions switch, and the throttle itself ALL on the left hand. I just cannot buy into this idea that people are functionally useless with their left hands.