I agree with post three. The doctors aren't killing people; they are simply saving as many as possible.
Think of it this way: Ten people are on a skiing trip and they all get caught in an avalanche and are separated. When Search and Rescue finds them all, say within a 1/4 mile of each other, two had food in their packs and space blankets with only minor cuts from debris (they can help each other), four have broken bones but had food and coats (need medical attention but not too seriously), five had food but little warmth and now have frostbite and beginning stages of hypothermia (need medical attention now, but will survive a trip to a hospital/trauma center), and one hotshot in all spandex with a backpack as light as possible, is barely breathing due to lack of food, warmth and severe hypothermia.
Morally, it is obvious to first attend to the less severely injured and get them to a hospital now, since the injured two have already taken care of themselves and are fine. Those with broken bones will survive a wait in a shelter until more emergency vehicles and personnel can arrive and take them to alternate hospitals. This leaves us with the last victim in the worst condition. He most likely will die of hypothermia before he can be helped and he is fading fast, so consequently, he is the last to be helped because he has the worst chance of survival, past medical availability.
So now with our triage, we have saved nine out of 10 possible where if we had helped the most injured, we may have only saved five, because the less severely injured people would not have received the attention that they needed in time, while the paramedics were struggling to keep the hotshot alive, and could easily move into a worse and eventually fatal condition.