What if it's like NV, where they can die if they aren't following you?
Then if you want them dead (in the event they get knocked out) just wait until the battle is over and they are conscious, fire them, and shoot them as they walk away. (you can bludgeon them if you wanna save ammo}

Focusing on more important, practical goals -- such as a practical, better-functioning A.I. -- instead of pursuing an impractical objective for A.I. is a good thing.

Theres an example/story on the FNV boards of companions being told to wait in the Lucky 38 suite and later being found dead, think it theorized one of them picked up an item (food?) from your stash and the others regarded it as theft and shot them.

Ah yes which goes back to my saying have all NPC's killable and develop the Artificial Intelligence (A.I.) system better.

you could still do all that even with immortal companions also companions can be knocked out during a fight and not recover untill after the fight or at least untill a stimpak is used on them so your companion wont be unstopable.

Well yes that is what I was talking about the immortal companions you send your unkillable companions to clear out bandit hideouts, etc.

why would anyone do that and expect them to take out the entire camp? Try that in skyrim and he/she would end up being downed constantly you would eventually get impatient and go see whats taking so long. Just because there immortal doesnt mean they will be unstopable hell they will probably have a run away feature when there life is to low or when there getting downed to often.

It doesn't go back to your idea. There are many different things A.I. can be used for, and catering to that one specific, personal preference of yours is just one of them. You feel that your goal is more important than any other goal the programmers might have had, but it appears that the designers thought otherwise.

Because there are people who like to use cheats or exploits and abuse them? Just take a look at the The Elder Scrolls V: Skyrim mods section on the Nexus mods website.

Every now and then you will see PC gamers who upload mods that make them be able to kill NPC's with one punch being unarmed or with one swing of a Elven mace, etc.

The dog being unkillable in Fallout 4 I'm willing to be there will be people who will use the dog to clear out bandit hideouts, even if it will take a long time, even if the dog will constantly get knocked out.

Im having a real hard time imagining anyone just sitting around waiting for there companion to finish off an entire camp of enemies for an hour and call it fun. And if people want to use exploits and cheats to win there battles they have no right to complain about the game being to easy because of immortal companions.

Of course people cheating or using exploits being easy to win a video game have no right to complain.

All I'm saying is I don't like Essential NPC's, protected NPC's or unkillable NPC's in video games and that I wish all NPC's are killable in Fallout 4, even if they become your companions or followers.

Hehehehe theres a reason bethesda made some npc's unkillable after morrowind.

Yes and I know what that reason is. I made mods to make them be killable again in The Elder Scrolls IV: Oblivion, Fallout 3, and The Elder Scrolls V: Skyrim.

I have the same save game I have been using since 2006 when I purchased The Elder Scrolls IV: Oblivion and only two Essential NPC's have died since 2006 from that same save game I play with every now and then.

It's indeed a "reload case" as Todd Howard said but I don't mind reloading if I failed.