If you put an eye in your leader, and then thread the eye through the hook from the front, around the bend,and then pull tight, you will have about 40% more hookups. See figure 1 in the link. While this study was done with tuna cord, it holds true for any stiff leader. by allowing the hook eye to move freely in the leader, you lose an advantage...

http://www.iphc.washington.edu/halcom/pubs/rara/2000RARA/RARA00_12.pdf