“Fishing the hang” is a simple trick for hooking a lot more fish
WHY IT WORKS
To understand fishing the hang, it’s helpful to think about how a sinking fly line—and thus your fly—behaves. When a sinking line hits the water, the whole length descends at the same rate, sweeping the fly and leader down with it. As you strip in line, the fly’s path is roughly horizontally until it’s almost back to you and rises steeply toward your rod tip. (The same thing happens with a weighted fly and a floating line, but since the fly doesn’t go very deep, the final rise is less dramatic.)
From underwater camera footage, we know that trout in lakes and ponds often follow baits for a long time without striking. Bass, pike, walleye and other fly-rod gamefish do the same thing. However, these followers are sometimes triggered to bite if the bait changes speed and direction, like a baitfish or insect moving toward the surface.
So, picture how a subsurface fly on a sinking line moves at a relatively consistent depth until near the end of the retrieve, when it scoots up toward your rod tip. That triggers the fish to attack, just as you’re flicking the line up and away. So instead of hitting steel, the fish strikes the spot where your fly was an instant earlier, leaving both parties frustrated and bereft (if for different reasons).