Dean Leffingwell is the creator of SAFe (Scaled Agile Framework) and founder of scaled-agile-inc. Leffingwell adopted Reinertsen's weighted-shortest-job-first prioritization and cost-of-delay framework as core practices within SAFe, giving these ideas their widest enterprise adoption.
Leffingwell's adaptation simplified Reinertsen's economic framework for large-scale enterprise use. SAFe's standardized WSJF formula makes the approach more accessible but arguably loses some of the nuance in Reinertsen's original — particularly around context-sensitivity and the judgment required to properly estimate cost of delay. Reinertsen's economic-framework-for-prioritization is designed as a reasoning tool; SAFe's version risks becoming a mechanical formula. Nevertheless, Leffingwell's incorporation of WSJF into SAFe has exposed Reinertsen's core economic thinking to a very large audience of enterprise practitioners. See leffingwell-safe-framework for the primary text through which this adaptation occurred. Reinertsen also wrote the foreword to Leffingwell's "Agile Software Requirements" (see leffingwell-agile-requirements-foreword), directly endorsing the WSJF transmission.