The reason you want to lower your rod or even lower it all the way in the water like the "pros" do is to try to prevent the fish from jumping at all. When you first set the hook, you pull straight up. This causes the fish to rush toward the surface and usually jump. When a fish jumps they are shaky their head back and forth trying to throw the bait and can easily get slack in the line. By them staying down and preventing them from jumping it is easier to keep pressure on them and prevent them from throwing the bait. I always lower my rod when I know I have a decent fish to keep them from jumping. Plus they have a lot of money riding on the line!!!!!