Personally I think a wide open stance for a 70-80 yard shot is overdoing it. It's not like a little green side shot where one totally legit mechanical option is to bring the feet closer together and have the toes both pointing well towards the target. Definitely some people play their wedges and even scoring irons with a slightly open stance, but not WAY open.
For me a 70-80 yard shot is close enough to full power that I just set up like I'm taking a full swing, maybe choke up a bit, take a 2/3-3/4 back swing, and come through smooth and easy. You're hitting easy but you still have to commit to the shot. One way to miss right with those is to get scared you're going to airmail the green, let the club head drag and never get it closed.