I don't fish for walleyes, but when we get a nice burbot on if its not hooked well we loose them right uner the ice while we are trying to turn them. having that trench hole, i would have caught alot of the ones i lost, less monkying with the head getting through, and less chance to cut off under the ice. So i would say you'll loose fish either way, do what you like to do best. I would like to trench them personally when there are bigger fish and there is a chance of getting one to big to fit. Also its exciting when you see the fish fighting below you.... my two cents