This also warrants some questions about the assumptions and expected behavior which feed into predictive aging approaches. Some of these challenges are: Can degradation chemistry be simply accelerated? Under which conditions do accelerated aging experiments lose their predictive value? How important are diffusion limited oxidation (DLO) complications? Can kinetic modeling provide predictive capabilities, and if so, where are the limits? What are the ongoing issues that need to be addressed to enable this research field to move forward?