Yeah I think the concussion mine is not meant to be a killing blow, but used to either displace enemies, or for you to use to get to hard to reach areas...

Given there are some cliffs and such to fall off of, it would be good to figure out choke points near areas where you could set that and knock your enemies off of a drop-off... I had rheinhart use his charge on me when my back was to a cliff and he carried me over the edge..