+1 realism and harshness
Noone cares about realism, so you can ignore this reason.
-1 abuse with RL/minigun/nade mercs
What? How this suggestion affects mercs with RL, nade miniguns and other weapon? No effect from this suggestion.
-1 affecting slaves
For slaves: what about them turning hostile after a bit more hit, but will stop if you use a new rope on them (no need to to knock them down).
Mercs, slaves, this suggestion was created only to stop "oops" in NCR, if slaves and mercs will have separate effects, then everyone will use the worst for them effect to continue abusing.
If rope will do it again allied with me, then I'll have to carry alot ropes with me when abusing them in NCR.
-1 I see no new fun in it
Me too, but those bluesuiters are unhappy when I killing them with this metod.
Some smart GM may ask:
"Why don't you simply stop doing that?"
My answer will be:
"Why should I, when it brings me alot fun? ^_^"