Do not cut the gullet or the fish will die. Leaving hook in and they will sometimes die but biologist say that if you leave it in and try not to tug on it too much the fish has a decent chance at survival. When doing this try to cut the line tag as close to the hook eye as possible. It has been proven a bass has a certain corrosive enzyme in their mouth and stomach that can rust out a hook in as little as 10 days or so.