Thought I'd share.
A friend who's a martial arts puff by day and security guard by night saw me reading this thread and exclaimed "now were talking" immediately when he saw this picture.
obviously there was lots of heartburn over my original lanyard with the 1.5" ball. this approach is a little more subdued; each 3/4" monkeys fist is a fob for individual keys. Also shown in tan is one "fob" with a 1" monkeys fist. combined with a heavy carabiner the whole end weighs just over 12 ounces. This is my keychain, it was made with a 3 strand braid. the manrope knot looks a bit different but works the same way.
So I asked why and he said the longs ones make a large arc, easy to pick and parry by reflex. Just grab the long line and you've basically disarmed your opponent, but the short one (according to him) produces 80% of the momentum of the big one, cannot be grabbed and is a lot more difficult to spot quick enough to parry.
I assume he pulled the percentages from his ... hat. Sure, longer radius of an arc reduces speed the ball travels that arc, but I still can't be bothered to try to figure out the math of skull crunching.
And I'm jealous of your knot making skills. Mine always end up twisting or uneven.
-jh