1) I never have been and probably never will be, a fan of learning anything off of a tape. Nothing can replace a live instructor.
2) Pressure points are, IMHO, not able to be taught from a tape.
3) I would suggest making sure that you are very justified in killing someone. For someone to think that they're going to be able to watch this tape, actually learn something, and if someone should happen to attack them, hit a point and kill the person...well, thats just an invite to spend some quality time in jail.
4) There are killing moves in pretty much every art. Why would I need a tape to learn this when the arts that I already study will do just fine, if that is something I needed to do?
My replies are not intended to come off as harsh, but I'm just giving my opinion. I would strongly suggest that if you are serious about learning an art, to find a teacher, rather than try to learn from a tape. As I said, nothing can replace a live teacher to show you the fine points of an art.