It looks similar to the 757 design. The 757 has two sets of cables going from the cockpit to the elevator actuators, one set for each pilot. The left pilot controls the left elevator, the right pilot the right. They are synchronized via a cam with a detent (notch) in it.

The detent connection enables one pilot to control the left and right cables. The idea is that if one set of cables jams, the pilot can still control his elevator by applying enough force to pop the cam out of the detent.

Of course, if both pilots pull hard enough in opposite directions, it will come out of the detent as well.

I was one of the engineers working on the 757 elevator system. I don't recall anyone talking about the possibility of the two pilots fighting each other for control. It was just inconceivable. Besides, both pilots would be able to feel the controls "popping" out of the detent. I doubt a warning horn would have made them less confused.

I don't know if pilot training included popping out of the detent so they know what it feels like, but it seems like a good idea.