I work 8h, 4 days per week. You learn to make meetings more effective, group menial tasks in to blocks and make time for interesting things, and become better

I work 8h, 4 days per week. You learn to make meetings more effective, group menial tasks in to blocks and make time for interesting things, and become better at prioritising. And damn do I feel productive when working on hard technical problems. Some things just require a fresh mind.