It's an old story that the top row of The Six Boxes Model generally provides more leverage than the bottom row. That's because the things we can do to change the environment (top row) are usually more powerful and broad-reaching than what we can do when we focus on the individual (bottom row).

The Checklist Manifesto: How to Get Things Right, by Atul Gawande, has had a much greater impact than simply on the field of clinical medicine, its birthplace.  As was noted by one of its reviewers when the book first came out in 2009, it represents a potential "game changer." That is, job aids offer the potential for improving performance with extreme cost-effectiveness, in this case literally saving lives.