Honestly, we all know that when a fish swallows the hook, or catches one in the gill...it's to be eaten or tossed back to die. If you cut the hook off, it has a LOT higher chance of survival. The hook may not decay, but the flesh/sore in the mouth will loosen the hook allowing the fish to spit it back out. Also, I have caught several healthy fish that already had another hook in inside their mouths, and every time, it's been rusty.
