We've already had a long discussion about throwing the Ka-bar, and the end result was a no, IIRC. It's not really made to be thrown, and generally militaries don't teach knife throwing, you'd have to go pick it up after one throw, coding/animating the throwing would make for even more work for the INF team which means later releases for 2.8/3.0 and it probably wouldn't be worth it all.
I don't know about you but I will probably make good use of the knife, especially in loadouts that include lots of explosives and such, I might decide to not take a pistol and some mags and to just go with the ligher, cheaper, knife for a backup weapon.
Oh, and as for the topic question: You can kill.
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Shot four puppet governors in a line,
Shook all tha world bankers, who think they can rhyme,
Shot the landlords, who knew it was mine,
Yes, its a war from the depth of time!