Your fishing rod is exquisitely strong, flexible. You have plenty of line, and with fighting fish it can withstand 100 kiloponds of pressure, but not more: jerks exerting that threshold will make the line break. So the way you set the action controlling your line is crucial to winning the fight: too loose, your adversary will just speed away, pulling your line with him, until it eventually breaks, abruptly. Too tight and the line will break immediately. The trick is to find just the right watershed setting for your action, not too tight, not too loose, just enough to withstand the jerks of the fish you are battling with. Say it’s a barracuda. When he wants to fight, give him a yard or two, but when he rests, you bring him in, 10 to 20 yards, until he jerks again, so you give him a bit, but not much, and when he rests after that, you bring him in more. You tire him out that way, until you have him close enough so that you can see your adversary’s silhouette glimmering below the surface of the water. Time to get your knife out and to prepare for that perfect single blow, that will take him out.
(I owe this story to Cyrus).