The Well-Planned Life is endorsed by Clayton Christensen, a professor at Harvard's Business School. Brooks graciously calls Christensen a Christian. Christensen is also a life-long Mormon.
The differences I see in both approaches makes the Well-Planned Life more consistent with Mormon beliefs.
The person leading the Well-Planned Life emphasizes individual agency, and asks, “What should I do?” The person leading the Summoned Life emphasizes the context, and asks, “What are my circumstances asking me to do?”
Since we believe that life, and our lives especially, were created with an overall purpose, we seek to mold our lives to that purpose. This is normative causing us to always ask, "What should I do?" and "What should we do?"