Actually i think 2 of those last ideas are a little off. Not that i am an expert but... Fish that bleed don't all die. I've caught rainbows that had holes in there heads/noses and fish with a single eye missing that were healed up. Just cause their in water doesn't mean their blood doesn't clot.<-not yelling) If it didn't they would all be hemopheliacs.LOL. Seeing a one eyed bow is strange and it surprised me, then i thought....how the hell did that thing live. They can fool ya.

Another is that hooks don't rust out in freshwater fish and i know you'll dissagree but they don't in saltwater either. They get pushed out naturally by the body healing the wound much like stories you hear of people getting glass or metal slivers stuck in their leg or thigh only later to have those same peices come out from the skin in a totally different area like their feet. Strange but it happens. I think the time it takes to heal the wound ultimately determines the fish's ability to eat. I know i couldn't swallow with a hook in my throat, and i doubt they can. Go barbless. It makes the healing process go much faster. If your really worried about it, then don't use bait.