Articles that describe plane disasters commonly talk about a pilot’s reaction that results in opposite course from what would have been a way out of a difficult situation. For example, when an airplane is loosing speed and starts nosediving, trying to pull it’s nose up only reduces the airspeed further and compounds the problem. Right action seems to be to nosedive and gain some speed and then have options at doing other things. Obviously, the correct action needs to be taken some distance before the ground.
Now, lets imagine a complicated situation of two planes on a collision course that simultaneously loose power and ability to maneuver right and left. The planes can adjust some altitude by using the nosedive maneuver to gain speed. So, there is some ability to move slightly up and slightly down while the airspeed still allows for gliding. If communications between the two planes occur ahead of time, there is a chance to agree on different altitudes to avoid collision. But, once the airspeed is near critical for one of the plains, the chances of positive outcome are diminishing exponentially. The results will be disastrous even if the second plane still has an option to nosedive to gain some speed. At late points, it would be impossible to avoid the collision because nosediving for the second plane only result in collision with the first plane that has not other course, but down.
Similarly, two people or two groups of people on a collision course have only a certain amount of time before collision is unavoidable. Communication ahead of time is the only solution to avoid a disaster. Don’t forget that we still did not figure out how the planes will land safely without the power.