I did some googling to see if I could find a research based look at different release methods, but couldn't find anything.
I have noticed however that in a lot of salt water fishing shows the host "torpedoes" the fish back, this may be due to the fish being unable to deal with temperature difference as stated earlier or may be due to the fish being unable to deal with pressure changes...
If anyone comes up with something objective, I'd love to see it.