There are ways to "take control" without physically fighting the pilot flying for the aircraft.
For example, during an unstabilized, out of parameters approach, the pilot not flying should make deviation call outs as per normal operations of the company. Then make it clear, "I feel uncomfortable continuing this approach, we should go missed." If the pilot flying displays an "I'm continuing no matter what" attitude, the pilot not flying may want to annouce a missed approach to the tower. At this point the pilot flying will go missed...
Just like the drunk pilot question. Obviously the drunk pilot is physically incapable of flying the airplane. That is close enough to "physically ill" to fit my definition. Tell the drunk to call in sick, or you'll call in sick (from concern over your license). Either way you have taken control of a situation without harming anyone's ego, or career.
It would not seem wise to physically take control of the aircraft, other than to apply the brakes if there is an instant threat of collision, or incursion.
During every flight, both pilots are responsible for ensuring clear communication. The best flight decks are managed with mutual respect.
It is appropriate to be matter of fact & directly communicate in the cockpit. It is never appropriate, or helpful, to get angry when flying.
And remember when the other pilot notices something you have overlooked - or is helpful with something you would not have caught - the response is "Thank You."
I've never had to take control of an aircraft, or vice - versa. Most folks want to fly the best they can and are willing to gladly accept constructive comments.
