i use a bowline knot (about 8") & stopper ball on my retrieval line too, to separate the top and middle patch on my mid pole system. if i used more than 8" the head of my spin would not go in the bag.

I do have my retrieval line reeved around 1 small block and 1 small metal ring on my rear beam/hiking straps to a. slow down my line when dropping & b. to avoid the line from twisting up. this all works pretty well.