I guess that depends on the species. If I see a sunny floating I don’t get as upset as if I see a bass or a walleye belly-up. I really have a problem seeing a gut-hooked fish that didn’t make the slot dead on the water . In my opinion acceptable mortality is zero but with slots and size regulations we are forced to throw dying fish overboard. I guess the DNR answers this question for us.
On Pool 2 that is 100% C&R, jigs 100% are released healthy. On cranks, maybe 90-95% are released w/out harm, the remainer have had hooks in their sides, eyes, or unfortuately gills. Hate to say it, but w/ current and multiple hooks, 1-2% of fish probably dont make it. Most the water I fish in under 10′, except in winter when the fish dont have to contend w/ warm water exhaustion.
Acceptable to me is zero, of course. Reality is, over the course of a season, it would not surprise me if 5% of ALL my fish caught died. It’s a nasty reality that likely would be much worse if efforts weren’t made to limit injury to the fish.
So is CPR a good thing? In my mind, without question it is. I know the mortality rate on a filleted fish is VERY high ( ) so I choose to focus on the good done in releasing the 95% that live vs. the 5% that don’t.