Generally hooks will break due to stomach acid, even stainless steel. They don't really rust out. Stomach acid has a PH of 1, which means it is even more corrosive than sulfuric acid in batteries.
If I can see the eye of the hook the gill plate method is the best.
Cider I'm going by an article I read some time back that studied the effects of fishing bass with shiner's in Florida. It was in infisherman and they found the bass had a great survival rate using the gill removal method. In fact they recommed it versus cutting the line. The fish they studied had inhaled the hook so only the eye was showing and the fish were tagged and caught again and again. I have just used that method based on the article and obviously haven't tracked the fish I caught and released but if done right it seems quick and painless.
Cider I'm going by an article I read some time back
Cider, I think we all agree with you,