It seemed like a joke to me.
Sure, while the fish is literally barfing up it's own esophagus and suffering the "bends", stab it in the side and punch a hole in it's air bladder. You know, the organ that keeps the fish's balance, equilibrium, and probably no worse off than the other organs in its body until you stab it. Assuming you hit it and not something else like say it's intestines, because it's really a narrow organ. The fish will be fine!
But apparently it works?
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