Why does it improve the accuracy of the experiment it Tf-Tr equals Tr-Tw?

When Tf-Tr equals Tr-Tw, it indicates that the temperature difference driving heat transfer is symmetrical, leading to a balanced system. This balance minimizes errors due to thermal gradients and ensures that the heat transfer processes are more consistent and predictable. Consequently, the experiment's accuracy improves as the results reflect a more stable and reliable thermal environment.