We have carried out a set of experiments to test the accuracy of two procedures, one suggested by Curro and Salazar and the other by Moacanin, Aklonis, and Landel, in predicting the behavior of polymer networks which are simultaneously chemically reacting and physically relaxing. The chemical reaction utilized was a photoinduced scission of disulfide linkages which had been incorporated into the network; thus the reaction could be turned on and off at will. The necessary input data to support the calculations were measured directly on the experimental samples under conditions where no chemical reactions occurred. Our results show that the behavior predicted by the technique of Moacanin et al. is in good agreement with that observed experimentally.