I don't know about dumb fish, but my first fish at Rocky Ford in Washington took a bead head pheasant tail nymph. I fought with him for a few minutes and *ping* he came unbuttoned. I watched as he swam away. I reeled in the line and found a hook that had straightened out. Hence the reason for loosing the fish. So I took my hemostats and put a curve back in the hook and cast to the same fish again. He took the fly again and this time I landed him. I wonder if he thought the second fly was any better than the first.