Over the last two winters the study involved the active participation of a meteorologist who initiated an evaluation of the road weather conditions each time a DOT participant submitted an Assessment of Recommendation report. The objective was to determine what factors were creating a disparity between what MDSS recommended and what users felt was a more appropriate maintenance action plan. The Assessment of Recommendation study made it clear that each situation has its own unique determing factors; however, the factors tend to cluster into four dominant classes: incorrect MDSS analysis and forecast of precipitation (especially snowfall), variances between actual and modeled blowing snow conditions, differences in the observed versus MDSS-derived pavement temperature, and disparities between actual maintenance practices and the configuration settings MDSS uses to simulate maintenance activities on the user’s route(s). This paper discusses the evolution of the Assessment of Recommendation study and looks at the predominant causes for differences between what the MDSS simulation generates and what MDSS users actually observe in the field. It will summarize potential modifications needed to improve the MDSS simulation process but also discuss ways DOT users can use the MDSS tool to achieve more effective decision support guidance.