i would say no because say if there was a 5 fish limit in an open, the first 5 fish you catch you're going to keep incase you dont get another 1. Then if you get your sixth, and its heavier, your going to replace it with the smallest one out of the 5 caught before, which would still mean killing/keeping fish, but your only going to weigh 5 in, so i don't think it would make that much difference. Also with the rate the trawlers bring them in, i dont think us anglers make that much difference.