In the document on the above link PIMA covers the following topics:
Enhancing Low-Slope Roofs with High Density Polyiso Cover boards: (Page 5) high density polyiso cover boards offer comprehensive strength that protects the low-slope commercial roof system from traffic, puncture, and hail damage.
Polyiso and Vapor Retarder Paradox: (Page 11) used correctly, vapor retarder materials like polyiso insulation can be an effective solution for moisture control. However, when employed incorrectly, it can contribute to moisture accumulation and prevent the structure from drying.
Energy Code Math for Commercial Walls: (Page 17) the use of continuous insulation (ci) systems on walls is changing the way specifiers, design professionals and builders look at the building envelope