I wonder how well those two released bass recovered from the angling experience since they were not released immediately back into the water. I say this because the back ground in the pictures were not on the water locations. I think we overestimate the vitality or recovery ability of old, overweight fish after they have been jaw jerked and harassed to exhaustion and then placed back into a harsh survival of the fittest environment. I am not saying what you are doing is wrong. I am just questioning the ability of big old fish to successfully survive intense jaw jerking episodes by sometimes less than the best of anglers that do not place the fish's health first.
The first bass held by its jaw is literally 3 feet from the pond. Landed it, snapped a couple pics, and released it by placing it in the water, holding it, slowing moving the water over its gills. It shot off right quick. You can see a mark on its side. That same toad was landed over 2 months later by a mate of mine. I recognized that mark in his pic.
The second bass inside is literally a 20 second walk from the pond. You saw the building in the other bass pic - the white stone exterior. It was taken inside to be weighed and then released in the same manner as the first. I know the owner and while fish can die and stay on the bottom there were no reports of any dead floaties.
I understand that picking up a bass by its jaw can due damage, and while not justifying it, I would also think that hooking a bass with a sharp steel hook and essentially dragging it against its will as it fights to go the opposite direction is also likely to harm it. So I don't know that picking it up at this point by it's belly will do any less harm than the possible traumatic experience of being hooked and drug through the water.
BTW, I understand you're not attacking me or saying I was wrong even if you think I was, and I hope my reply isn't interpreted as a defensive attack. Online forums don't convey the intent and expressions that face to face conversations do.
