There is no "kill" in the AMA/RCCA rules. You keep flying even if you loose your entire streamer. Also, all cuts count the same, so if you take just a few inches off the end of an opponents streamer with your prop, that's 100 points. If you take the whole streamer in one pass, that's 100 points. (so it's actually better to just take a little, so you an come back later for seconds).