AverageJoe, both your examples show the fish coping quite well with hooks( jigs )in 'em.
Now, as far as them not disolving, until you can determin how long a hook has been in a fishes mouth, you can't say it doesn't disolve. In your one example, we only know that they don't disolve in a week.
Sometimes, harvesting is not an option because of slots etc. so I would much rather cut the line.