Putting in 6 days to get 3 is a -50% ROI, not much better than -60% ROI of the five-day work week. I propose Profito: A 3-day week for a profitable life. For every 3 days you work, you get 4 days free.
In many competitive professions, your outcomes are based on your rank, or it is winner take most after a cutoff.
So sometimes being 1 percent better gives 1000x rewards.