This paper is a re-evaluation of heat-aged test data reported in a recent study by Dixson and Nelson (1). The study presents much worth-while data. However, the method selected for plotting the folding endurance and tear resistance data is not always reliable and, therefore, many of the conclusions drawn were based on inaccurate evidence. When the data are replotted appropriately on semilogarithmic graph paper, values on the regression line are compatible with those in previous studies made by Barrow (3). The data properly projected show that writing papers follow a deterioration pattern during extended heat aging similar to that of book papers.