Not if you have white collar standards for "sportsmanlike behavior" it's not.

That said, I agree with you. If I want X pounds per year of venison I'm gonna get it and I see no reasons to spend a few hours sitting in the woods during a particular part of the year to do it.

Run a wire around the perimeter near the top with a fence charger attached and you'll solve that one quickly.

Metal fences are tricky for groundhogs. my parents have one that is welded wire (comes in a roll) and its not sturdy enough for a fat groundhog to climb all the way up and get over, they aren't the most athletic. once they shored up some holes along bottoms of the fence the groundhog wasn't getting inside anymore.